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Medical Forum / General / Vision / March 2005No genes for myopia and only poor science to say its genetic.
"RM" <privacy@piracy.net> wrote in message news:<d188hq06k0@enews2.newsguy.com>... > The genetic basis of myopia is known. What is also known is that genetics > is not everything. I offer the following starting information for you. > You can "Google" and "PubMed" yourself for lots more details. Ok. As you suggested i have done all that you asked. ****None**** of this stuff provides any evidence of myopia being genetic. Science is still looking and wondering. A summary. 1.There seem two be two myopias - familial and school myopia. Young TL has only so far identified candidate or possible genes. As of this morning a well known British myopia researcher confirmed this to me. "****If**** we can find myopia susceptibility genes, we ****may*** be able to work out why myopic eyes grow excessively large. ****Then*** we can work on finding therapies to stop this enlargement happening. I agree with you that classical twin studies probably over-estimate genetic effects due to the Common-Environment Assumption (CEA). " The details: 1. Familial or high myopia. Relatively rare and **possibly** linked to genes. Prog Retin Eye Res. 2005 Jan;24(1):1-38. How genetic is school myopia? "The chromosomal localisations characterised so far for high familial myopia do not seem to be relevant to school myopia" *****but****** From the horses mouth last year. Trans Am Ophthalmol Soc. 2004;102:423-45. Dissecting the genetics of human high myopia: a molecular biologic approach. Young TL. "Identifying the implicated genes for myopia susceptibility **will** provide a fundamental molecular understanding of how myopia occurs and ***may*** lead to directed physiologic (ie, pharmacologic, gene therapy) interventions. The purpose of this proposal is to describe the results of positional **candidate** gene screening of selected genes within the autosomal dominant high-grade myopia-2 locus (MYP2) on chromosome 18p11.31." 2. School myopia. What most myopic people have and not linked to genes. Prog Retin Eye Res. 2005 Jan;24(1):1-38. How genetic is school myopia? "High heritability values are obtained from twin studies, but rest on contestable assumptions, and require further critical analysis, particularly in view of the low heritability values obtained from parent-offspring correlations where there has been rapid environmental change between generations." > 1. A well known genetic basis is evident by comparing myopia incidence in > persons of Asian descent versus persons of European descent. The difference > is something like 70% vs. 30%. This is true regardless of "environment" > since Asians living in the US or Europe still have the same high rates of > myopia versus the native population and vice versa. This one is simple. China mainland with billions has low myopia. Taiwan with millions has high. > 2. The studies of Young et al. which have identified the locations of > specific genes on human chromosomes that relate to myopia development. See > these two references: > Young, T.L., Ronan, S.M., Drahozal, L.A., Wildenberg, S.C., Alvear, > A.B., Oetting, W.S., Atwood, L.D., Wilkin, D.J., & King, R.A. (1998). > Evidence that a locus for familial high myopia maps to chromosome 18p. > American Journal of Human Genetics, 63, 109-119. I could not find this but in 2004, young says he is still looking. > Young, T.L., Ronan, S.M., Alvear, A.B., Wildenberg, S.C., Oetting, W.S., > Atwood, L.D., Wilkin, D.J., & King, R.A. (1998). Second locus for familial > high myopia maps to chromosome 12q. American Journal of Human Genetics, 63, > 1419-1424 In the summary he says he finds evidence. In a court Evidence carries the same weight as me being in NYC when a murder is committed. Anyway by 2004 he decided he needed better evidence - me being in brooklyn for example. > 3. Finally, there are population studies that show that myopia > development correlates best with parents who have myopia, and/or siblings > that have myopia. This correlation is much stronger than prolonged > near-work, and other factors. See the following two web references: > > http://www.optometryonline.net/news/article.cfm?ID=504 This begins with St Thomases twin studies. They use the flawed EEA. This article is just a press release to justify their research - probably due to the criticism they must surely have received for using the EEA method. > http://researchnews.osu.edu/archive/myokid.htm This is a strange one! Its a study of hundreds of kids which does not seem to include parents. "The researchers found that, per week, myopic children spent more time studying and reading for pleasure and less time playing sports than non-myopic children." They conclude that myopic parents have myopic children but dont otherwise reference the parents. Maybe you get better eyesight if you play more sport and are more socially gregarious? So to summarise: Still no evidence of myopia being genetic. And a bit of evidence that playing sport might improve your eyes. Maybe i should offer a significant cash price to whoever can come up with any evidence at all its genetic?? Everybody knows its genetic! Everybody! Doh! Andrew > So to summarise: > > Still no evidence of myopia being genetic. Really? Well the last I checked if there are GENES that have been located and that correlate with the development of high myopia, that's called GENETIC. So maybe "familial" high myopia is a different beast than "school myopia" but it's better proof that believing that stress or parental conflicts causes anything. I'm sure myopia is not a simple disorder. I'd bet that it's polygenic And why is it that Asian Americans who are living in the states have the same high incidence of myopia as do their ancestors in the Far East while North Americans/Europeans have a much lower incidence. It's not diet, it's not culture. Why is it that Americans living in Asia have the same lower incidence of myopia while all the native around them have a much higher incidence. It's not diet, it's not culture. And I'm not sure why you believe the incidence of myopia in mainland China is low. Maybe it's not as high as has been reported for Taiwan but it's much higher than North American/Europeans. Here's a quote from a mainland Chinese news report: "According to statistics compiled from a national investigation into student health, the myopia rate for Chinese primary school students is 22.78 percent, 55.22 percent for junior high school students, and 70.34 percent for senior high school students" .... " From 2000 to 2002 the near-sighted rate of junior middle school students in Taiyuan, Shanxi Province increased from 61.3 to 64.2 percent..." Sound pretty high to me. And why is it that in population studies there is continually a high correlation of myopia in children whose parents are also myopic? Oh. And I guess that we'll just have to totally disregard all the twin studies because you have an argument that you think totally discredits them and nullifies their conclusions-- Not! It's a valid argument that you have about the studies but the result is still out there and it's evidence on the side of a possible role of genetics. No one said genetics is the ONLY cause of myopia. No one said it's even the MAJOR cause of myopia. But it's clear that there is clearer proof of it having a role than for any of the factors you would have us believe. Don't get too stressed out Andrew-- I can imagine the axial length of your eye is already starting to increase! > Maybe i should offer a significant cash price to whoever can come up > with any evidence at all its genetic?? > > Everybody knows its genetic! Everybody! > > Doh! =================== Andrew, Here's something that "a well known American myopia researcher" from the Midwest just sent me. Haven't read them myself but I'm sure you will let us all know your critique. Mutti et al. 1996. Invest Ophthalmol Vis Sci 37:952-957 Zadnik et al. 1994. Jour. Amer. Med. Assoc. 271:1323-1327 RM No specific genes have been found. No Study yet available says that genes have been found. And as of this morning none had been reported on the scientific grapevine. People are looking and they feel they are getting closer and that is what is being reported. My myopia researcher contact also made the point that even if a gene is found it only could mean that myopes tend to experience anxiety more than normal sighted people. Even if a gene is found the argument over nature versus nurture will continue. Pre westernised Eskimos for example had little myopia. That does not change because a gene is found. Your two studies are literature reviews only One has the title "Myopia. The nature versus nurture debate goes on" I think it would be helpful if you were to read this study before you comment further. Your other study is called "The effect of parental history of myopia on children's eye size" In an environmentally determined cause of myopia involving anxiety and stress it would be expected that anxious and stressed myopic parents would have anxious and stressed myopic children. That in essence is the 'nature versus nurture argument'. To say it is genetic you need to have a method which eliminates environmental influcences that will alter the results in a significant manner eg large numbers of identical twins raised in different homes from birth - but this almost never happens. I agree that a quick review of the literature is now showing that myopia is increasing alarmingly amongst mainland chinese as shown by your media report. However Singaporean Indians have exstremely high myopia compared to Continental Asian Indians. Its just not as clean cut as you are suggesting. Naturally Asians in America tend to bring their culture with them to some extent. Also the life of an immigrant family is often stressful. Isolation racism and so on. These factors have to be considered to get meaningful results. I think i need a break from this unless you can come up with some scientific studies you have read personally and feel are relevant to prove your argument myopia is genetic. There is no evidence so far. At all. Andrew > prove your argument myopia is genetic. There is no evidence so far. At > all. > > Andrew You are incredible! I give you published references that point to pieces of DNA which segregate out with myopia in affected families and you don't call that evidence. Then you ignor the whole Asian vs. European population incidence argument. Then you quote one argument that others have made against the twin studies and state that it therefore totally refutes the conclusions. Then you ignor the fact that myopic children seem to come from myopic parents. And you conclude that there is no evidence whatsoever that genetics has a role in myopia!!-- Simply incredibe. Apparently you want to set the bar for accepting evidence very very very high. And the evidence that stress has a role in myopia is what now-------- waiting! I think you do need a break Andrew. We all do. > > prove your argument myopia is genetic. There is no evidence so far. At > > all. [quoted text clipped - 4 lines] > DNA which segregate out with myopia in affected families and you don't call > that evidence. It appeared clear from the studies that i found and showed here that the most common form of myopia is not being examined by gene studies. Why do you now ignore that? Your references were only for the less common familial (high and quick onset?) myopia - not the much more common childhood myopia. Other references provided by you but unread by you showed that there was a debate still 'raging on'. Between Geneticists and those who say the science is flawed. But in any case I could not see that any genes had been found. It appeared suspected clusters might have been located. I think it would a useful line of enquiry for me to find out more about so called familial myopia. Clearly if an eye is born with major genetic defects its outside of the line of enquiry i am involved in where myopia tends to decrease with age, or can appear at more or less any age from birth to death. Ie its so random that genetic affects are small or unlikely to be operating. As for myopic parents and myopic children. Similarly black children were regarded as inferior in intelligence because black parents who did not score well on intelligence tests produced children who did not score well on intelligence tests. Whatever the truth any test method that does not look at environmental factors (and they are not simple) is unscientific in its design. No amount of huffing and puffing changes these facts Andrew . > It appeared clear from the studies that i found and showed here that > the most common form of myopia is not being examined by gene studies. > > Why do you now ignore that? That is not what we were discussing. You stated that there was no evidence that genetics has anything to do with myopia-- which is clearly an untenable position (as we both know). Give it a rest Andrew. > RM > [quoted text clipped - 54 lines] > > Andrew I concur with you needing a break from this. Your efforts to come up with a universal developmental theory for physical changes which excludes genetic influences are understandably frustrating and doomed to failure. It is literally incomprehensible to me that you would have squandered so much time and effort on this idea. DrG > > RM > > [quoted text clipped - 67 lines] > to failure. It is literally incomprehensible to me that you would have > squandered so much time and effort on this idea. Dear Dr G Somewhere in this puzzle it is possible there may be some genetic factor operating. Evidence which withstands scrutiny is all that I would like to see. Meanwhile if you can provide me with a reference that shows a clear statistical genetic influence that is not produced on a false assumption ***or*** you can tell me why you believe that such assumptions are not false that would perhaps still be a useful line to pursue. Thanks Andrew >> > RM >> > >> > No specific genes have been found. No Study yet available says that >> > genes have been found. And as of this morning none had been reported >> > on the scientific grapevine. Actually, an number of genes have been identified as involved in refractive error. However, refractive error has many causes and you are not going to find a single cause. You are searching for evidence that anxiety causes myopia and you continue to try to infer that from any study you read. If you start with the assumption that all myopes are anxious, then you are always going to be able to say that myopic parents have an anxiety gene, not a myopia gene that they pass on or that myopic parents create an anxious environment that their children grow up in. It is a self fulfiling prophecy, not science. If you truly want to know the cause of myopia (ie are not just searching for evidence that anxiety is the cause) then you need to lose your bias and read the literature for what it is, not what you hope it is. There has been little research correlating anxiety and myopia, a MedLine search yielded fewer than 20 hits, the bulk about controlling anxiety during LASIK surgery. Those that did had few subjects and found no relationship, like this one: Myopia in optometry students: family history, age of onset and personality. Bullimore MA, Conway R, Nakash A. School of Optometry, University of California, Berkeley 94720. The relationship between refractive error and family history, age of onset and personality was investigated in 189 optometry students. Subjects completed a questionnaire requesting details of their refractive history, type of correction and their family history. Subjects also completed an Eysenck Personality Inventory (EPI). Subjects were categorized as hyperopes, emmetropes or myopes on the basis of their questionnaire responses. No significant relationship was found between refractive group and the prevalence of myopia in parents. Myopic subjects, however, showed a significantly higher prevalence of myopic siblings. Furthermore, late-onset myopes showed a higher prevalence of myopic siblings than early-onset myopes. No significant personality differences were found between the refractive groups. And here is a study, with lots of subjects, about genetics and myopia: 1: Invest Ophthalmol Vis Sci. 2005 Feb;46(2):442-6. Related Articles, Links Support for polygenic influences on ocular refractive error. Klein AP, Duggal P, Lee KE, Klein R, Bailey-Wilson JE, Klein BE. Statistical Genetics Section, Inherited Disease Research Branch, National Human Genome Research Institute, Baltimore, Maryland, USA. PURPOSE: Refractive errors, myopia, and hyperopia are common conditions requiring corrective lenses. The familial clustering of myopia has been well established. Several chromosomal regions have been linked to high myopia (12q, 17q, and 18q), to quantitative refraction among twins (3q, 4q, 8p, and 11p), and to families with moderate myopia (22q). This study examined the familial aggregation and pattern of inheritance of ocular refraction in an adult population, by using data from the Beaver Dam Eye Study. METHODS: Familial correlations were examined and segregation analysis was performed on the average refractive error measurements in the right and left eyes after adjustment for age, sex, and education. Analyses were based on 2138 individuals in 620 extended pedigrees with complete data on age, sex, education, and spherical equivalent. RESULTS: Substantial positive correlation was found between siblings (0.33), parents and offspring (0.17), and cousins (0.10) and lower correlation among avuncular pairs (0.08) after adjustment for age, sex, and years of education. The results of this segregation analysis do not support the involvement of a single major locus throughout the entire range of refractive error. However, models allowing for familial correlation, attributable in part to polygenic effects, provided a better fit to the observed data than models without a polygenic component, suggesting that several genes of modest effect may influence refractive error, possibly in conjunction with environmental factors. CONCLUSIONS: These results support the involvement of genetic factors in the etiology of refractive error and are consistent with reports of linkage to multiple regions of the genome. > Actually, an number of genes have been identified as involved in refractive > error. However, refractive error has many causes and you are not going to > find a single cause. Dear Dr Judy Thanks for your reply. You have quoted a study that claims genes are found but so far i have not sighted those actual studies that show genes are found. It appears one of the leading researchers into genes and myopia is still looking for specific genes has some 'candidate genes' and feels he will find genes. There also appears to be the issue of: 1. familial myopia (which appears to be a sudden onset high myopia appearing in the very young and clearly linked in some manner to similarly myopic parents) and 2. Common or school myopia which is not clearly linked to myopic parents. > You are searching for evidence that anxiety causes myopia and you continue > to try to infer that from any study you read. If you start with the > assumption that all myopes are anxious, then you are always going to be able > to say that myopic parents have an anxiety gene, not a myopia gene that they > pass on or that myopic parents create an anxious environment that their > children grow up in. It is a self fulfiling prophecy, not science. There are large numbers of references in the literature to myopia being related to anxiety and that hyperopia is not related to anxiety. For example: 1. Myopia Palmer (1966,1970) "Myopes present an outward appearance of calmness" "but tend to be suppressors of potential anxiety" "Myope does not respond impulsively, but is instead, quite cautious" Schapero and Hirsch,1952 myopes are "emotionally unresponsive, unexcitable, highly controlled" Van Alphen et al 1952 myopes "have deep rooted anxiety Rosanes 1966 "they have a low tolerance for anxiety and want to stop any situation they find threatening or stressful" Young 1966 "defending their ideas when attacked" 2. Hyperopia Schapero and Hirsch 1952 "carefree lively and impulsive" "socially passive" Young 1966 "having a high need for exhibition and change" Then there are doctoral dissertations Kelley, Charles R. "Psychological Factors in Myopia." Ph.D. dissertation. New School for Social Research, New York: 1958. Fox, Jack. "Functional Factors in Myopia." Ph.D. dissertation. UCLA: 1958. A PSYCHOLOGICAL APPROACH TO THE IMPROVEMENT OF MYOPIA.. ZEIGER, CAROLYN ALLEN, PHD. UNIVERSITY OF COLORADO AT BOULDER, 1976. 262 pp. THE VISUAL ANOMALIES OF MYOPIA AND HYPEROPIA RELATED TO PSYCHOLOGICAL FACTORS.. BRANDT, ROBERT, PHD. CALIFORNIA SCHOOL OF PROFESSIONAL PSYCHOLOGY - BERKELEY/ALAMEDA, 1977. 158 pp. Gottlieb, Ray. "The Psychophysiology of Nearsightedness." Ph.D. dissertation. Berkeley: 1978. McClay, William H. "Systematic Relaxation: A Treatment for Visual Problems." Ph.D. dissertation. United States International University, San Diego: 1978. FAMILY CHARACTERISTICS RELATED TO THE DEVELOPMENT OF MYOPIA.. GRIGSBY, EUGENE HOWARD, PHD. WASHINGTON STATE UNIVERSITY, 1979. 90 pp. PSYCHOLOGICAL CHARACTERISTICS OF BOYS WITH MYOPIA. SEITLER, BURTON NORMAN, PHD. FLORIDA INSTITUTE OF TECHNOLOGY, 1981. 242 pp. MYOPIA AND PERSONALITY: A COMPARATIVE ANALYSIS OF MYOPIC SUBGROUPS. CARLIN, ENID SUSAN, PHD. UNIVERSITY OF GEORGIA, 1981. 77 pp. Kellum, R.B. Capitalism and the Eye. Ann Arbor, Mich.: UMI Dissertation Information Service, 1997. Now some of these PhD's may well be micky mouse ones. But not all are. Kelly is still alive but he has got into some really flaky personal research on 'energy weather prediction' which makes the work he did earlier seem like the work of a lunatic. However his fundamental findings of former times seem to have a great deal of merit in my view. He was one of the first to associate myopia with anxiety, anger with hypermetropia and confusion with astigmatism. Ie different refractive errors have different personality/mental causes. I have spoken to Dr Burton Seitler who is now a practicing psychoanalyst who remains interested in the topic (the only normal sighted child of a myopic family) and he seemed a normal kind of guy and not your average nutty or eccentric shrink. I also emailed quite a bit with Dr Carolyn Zieger (a myope) who is now working as a practicing psychotherapist who now feels diet is more likely to be a factor. However i spoke to her Supervising professor , Lew Harvey Jnr (myope) who is a respected and well known professor of visual percption who felt the work had merit and should be followed up but he was no longer interested personally. Then there is the modern and ongoing work of Roberto Kaplan a former prof of optometry who is the most outstanding present figure in this field of relationships between prescription and behaviour. He has published 3 books which provide more references. I have met him and he is undoubtedly authoritative and very convincing even for those who have no awareness of this subject. He visits london once a year or so. http://www.beyond2020vision.com/healthyemotions.html http://www.beyond2020vision.com/lightlensesmind http://www.beyond2020vision.com/nearsightedness1 http://www.beyond2020vision.com/nearsightedness2 > If you truly want to know the cause of myopia (ie are not just searching for > evidence that anxiety is the cause) then you need to lose your bias and read > the literature for what it is, not what you hope it is. It would appear evident that i have read some literature which you have not read. >There has been > little research correlating anxiety and myopia, a MedLine search yielded [quoted text clipped - 17 lines] > significantly higher prevalence of myopic siblings. Furthermore, late-onset > myopes showed a higher prevalence of myopic siblings than early-onset > myopes. No significant personality differences were found between the > refractive groups. Dr Judy We tend to interpret data as we want to interpret data. I found the above very very interesting "No significant relationship was found between refractive group and the prevalence of myopia in parents. Myopic subjects, however, showed a significantly higher prevalence of myopic siblings. Lets be clear. 1. No significant relationship between myopia in parents 2. Myopes were highly significantly likely to have myopic siblings. Does that not strongly suggest a common environment for those children? If myopia were inherited in this manner people would quite quickly be showing returns to normal sight. Instead in single generations societies show massive increases in myopia. > And here is a study, with lots of subjects, about genetics and myopia: > [quoted text clipped - 11 lines] > requiring corrective lenses. The familial clustering of myopia has been well > established. Yes that is true. But this does not mean it is genetic. Several chromosomal regions have been linked to high myopia > (12q, 17q, and 18q), to quantitative refraction among twins (3q, 4q, 8p, and > 11p), and to families with moderate myopia (22q). Please show me the studies that do make this linkage. Are we talking about linkage or **candidate** linkage as described by TL Young in 2004? > This study examined the > familial aggregation and pattern of inheritance of ocular refraction in an [quoted text clipped - 3 lines] > after adjustment for age, sex, and education. Analyses were based on 2138 > individuals in 620 extended pedigrees with complete data on age, sex, > education, and spherical equivalent. RESULTS: Substantial positive > correlation was found between siblings (0.33), parents and offspring (0.17), > and cousins (0.10) and lower correlation among avuncular pairs (0.08) after > adjustment for age, sex, and years of education. Once again the results are very interesting. Parent child correlation is quite low at .17 whereas sibling correlation is two times that. That to me is a strong argument for environmental factors. >The results of this > segregation analysis do not support the involvement of a single major locus > throughout the entire range of refractive error. True. Its clearly not strongly genetic >However, models allowing > for familial correlation, attributable in part to polygenic effects, This is an assumption or model. An assumption that familial correlation is genetic correlation. > provided a better fit to the observed data than models without a polygenic > component, suggesting that several genes of modest effect may influence > refractive error, possibly in conjunction with environmental factors. > CONCLUSIONS: These results support the involvement of genetic factors in the > etiology of refractive error and are consistent with reports of linkage to > multiple regions of the genome. Their conclusion is based on an assumption. Ie familial correlation is genetic correlation but no assumption is made about environment (for example) which provides a far better fit. We all have biases. Whatever my biases all i am looking for is some study that can be fairly examined and shown to withstand that examination Andrew >> Actually, an number of genes have been identified as involved in > refractive [quoted text clipped - 7 lines] > found but so far i have not sighted those actual studies that show > genes are found. snip > 1: Invest Ophthalmol Vis Sci. 2005 Feb;46(2):442-6. Related > Articles, snip > Several chromosomal regions have been linked to high myopia >> (12q, 17q, and 18q), to quantitative refraction among twins (3q, 4q, [quoted text clipped - 4 lines] > about linkage or **candidate** linkage as described by TL Young in > 2004? Pay PubMed for a complete copy of the paper whose abstract I posted. The reference list of the study will cite the studies that found the genes. You can then find those studies for the answer to your questions. snip > There are large numbers of references in the literature to myopia being > related to anxiety and that hyperopia is not related to anxiety. snip of studies and PhD dissertations from the '50s, '60s and '70s You might want to look at more recent work. Thirty to fifty years ago anxiety and poor parenting (especially "cold" mothers) were blamed for many conditions like schizophrenia, depression, homosexuality, anti social behaviour that are known to be either genetic variations in brain chemistry or due to slow acting viruses affecting brain chemistry. Kaplan's work has not been published in peer reviewed journals, at least I could not find any. > Whatever my biases all i am looking for is some study that can be > fairly examined and shown to withstand that examination No one study proves anything in science. It is the body of evidence about a particular subject, taken in totality that forms the current opinion. Dr Judy > >> Actually, an number of genes have been identified as involved in > > refractive > >> error. Dr Judy, This is incorrect. I have a contact in Britain so I do not know what i am saying here. Several times i have attempted to explain the state of science to date. 1. Terri Young has investigated pathological high myopia in relatively small sets of families that is assumed to be genetically related and found some evidence that chromosomes 18P and 12Q are involved 2. Others have not been able to repeat this work for very large sample sizes of low to medium myopes 3. One study of high myopes did not found 18P 12Q relationships but did find a relationship on 'the long arm of 17' At the moment this is a very young science and no genes have been found that are statistically linked to myopia. Earlier I said >> You have quoted a study that claims genes are > > found but so far i have not sighted those actual studies that show [quoted text clipped - 4 lines] > > 1: Invest Ophthalmol Vis Sci. 2005 Feb;46(2):442-6. Related > > Articles, I think i was unclear. This study ***says** chromosome ***regions*** have been linked to high myopia. And i have addressed that above. As you correctly point " It is the body of evidence about a particular subject, taken in totality that forms the current opinion." > snip of studies and PhD dissertations from the '50s, '60s and '70s I had 80's studies and a 1997 study amongst the things you have cut out. > You might want to look at more recent work. Thirty to fifty years ago > anxiety and poor parenting (especially "cold" mothers) were blamed for many > conditions like schizophrenia, depression, homosexuality, anti social > behaviour that are known to be either genetic variations in brain chemistry > or due to slow acting viruses affecting brain chemistry. In reality what you are saying is just not true. Schizophrenia for example is now regarded amongst many reputable scientists as being a condition that arises in families due to the way families communicate with and condition their chidren. Homosexuality too is also an issue that continues to create controversy. These issue are not as cut and dried as you imagine. > Kaplan's work has not been published in peer reviewed journals, at least I > could not find any. Did you click on any of the links i gave you? Kaplan R. M. Nearsightedness - Seeing Beyond The Obvious - J Optom Vis Dev. Summer, 2003; 34 ( 1):24-30 Kaplan R. M. Light, Lenses and The Mind -The Potent Medicine of Optometry J Optom Vis Dev. Autumn, 2002; 22 ( 4); 153-160. Roberto M. Kaplan, O.D., M.Ed., FCOVD. To summarise this very briefly for those in a hurry. 1. In certain closed genetic groups such as the Amish, and parts of the Jewish community high myopia > -6 has been investigated for chromosomal linkage. These studies use relatively small numbers of families. Statistically significant linkage has been found for **different** chromosomes in **different** studies. 2. In **bigger studies** involving low to medium myopes **no link** to chromosomes for the same high myopia chromosomes have been found 3.Candidate chromosomes and candidate locus (gene locations) are continuing to be sought. 4. Various studies have linked high myopia to several Chromosomes but so far **no two studies have so far repeated the other studies results**. 5. finally it has to be pointed out that using unusual and closed communities who are significantly behaviourally different from joe public to exam genetic linkages seems a bit suspect but even so no genes have been found. Andrew > Somewhere in this puzzle it is possible there may be some genetic > factor operating. Thank you Andrew. You have finally been forced to state the obvious. who are you to decide what good vs. bad science is. you who believes that myopia is caused by penis envy or some other kind of psychological crap. doo.. > who are you to decide what good vs. bad science is. > > you who believes that myopia is caused by penis envy or some other kind > of psychological crap. > > doo.. RM suggested to me that the work of Young showed myopia was genetic. Perhaps i could invite you to read this research abstract and then explain to me where it says that genes for high myopia have been found. "http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstra ct&list_uids=15747770 Trans Am Ophthalmol Soc. 2004;102:423-45. Dissecting the genetics of human high myopia: a molecular biologic approach. Young TL. Department of Ophthalmology, University of Pennsylvania, and the Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, USA. PURPOSE: Despite the plethora of experimental myopia animal studies that demonstrate biochemical factor changes in various eye tissues, and limited human studies utilizing pharmacologic agents to thwart axial elongation, we have little knowledge of the basic physiology that drives myopic development. Identifying the implicated genes for myopia susceptibility will provide a fundamental molecular understanding of how myopia occurs and may lead to directed physiologic (ie, pharmacologic, gene therapy) interventions. The purpose of this proposal is to describe the results of positional candidate gene screening of selected genes within the autosomal dominant high-grade myopia-2 locus (MYP2) on chromosome 18p11.31. METHODS: A physical map of a contracted MYP2 interval was compiled, and gene expression studies in ocular tissues using complementary DNA library screens, microarray matches, and reverse-transcription techniques aided in prioritizing gene selection for screening. The TGIF, EMLIN-2, MLCB, and CLUL1 genes were screened in DNA samples from unrelated controls and in high-myopia affected and unaffected family members from the original seven MYP2 pedigrees. All candidate genes were screened by direct base pair sequence analysis. RESULTS: Consistent segregation of a gene sequence alteration (polymorphism) with myopia was not demonstrated in any of the seven families. Novel single nucleotide polymorphisms were found. CONCLUSION: The positional candidate genes TGIF, EMLIN-2, MLCB, and CLUL1 are not associated with MYP2-linked high-grade myopia. Base change polymorphisms discovered with base sequence screening of these genes were submitted to an Internet database. Other genes that also map within the interval are currently undergoing mutation screening. Andrew, You have no understanding of the difference between chromosomal loci (large pieces of DNA whose genes are yet uncharacterized) and the holy grail "myopia gene" (the actual protein encoding segment of DNA within a large segment in which mutation have been shown to cause a specific phenotypic change). The fact that specific chromosomal loci are known that segregate completely with the inheritance of myopia is sufficient evidence of a genetic basis of the disease. Just because we don't yet know exactly what the needle in the haystack is, i.e. what the encoded protein is and how it is mutated, doesn't mean we don't know that it relates to genetics. Knowing that a segment of DNA correlates 1:1 with the development of myopia is stronger than twin studies since there is no chance for arguments about common environmental influences. I'm tired of trying to make you understand even the most obvious of points. I've got better things to do. The truth is you don't want to understand. You are just another Otis-- argument for the sake of argument without regard for real data. An what is the data that proves stress has anything to do with myopia development? And why do many tribes of American Indians have high astigmatism-- is it that they ALL have conflicting messages from their parents? > You have no understanding of the difference between chromosomal loci (large > pieces of DNA whose genes are yet uncharacterized) and the holy grail > "myopia gene" RM earlier you told me >>> 2. The studies of Young et al. which have identified the locations of > specific genes on human chromosomes that relate to myopia development. See > these two references: Now you prefer to ignore that erroneous statement and instead tell me I cannot work out the differences between loci and specific genes > The fact that specific chromosomal loci are known that segregate completely > with the inheritance of myopia is sufficient evidence of a genetic basis of > the disease. This may be so. However it is only true for familial myopia whichy is an **unusual** rapid onset myopia commonly observed in the young and different to common school myopia > I'm tired of trying to make you understand even the most obvious of points. ?? Another alternate reality dweller > I've got better things to do. The truth is you don't want to understand. Good grief. I want to understand. Its you who seem determined to convert 'Loci' into 'specific gene' and exstrapolate unusual myopia to common myopia > An what is the data that proves stress has anything to do with myopia > development? Have a look at what i replied to Dr Judy > And why do many tribes of American Indians have high astigmatism-- is it > that they ALL have conflicting messages from their parents? Its like this. "Great God in sky say that Redman is free man. Great God say that all peoples of world are free. White man say America free country. White man say people in other countries are not free. Bad people in other countries. Oh Great God in Sky my spirit is not free! I live like trapped animal on reservation provided by white man. All people are free! My spirit burns with the anger of my ancestors! My honor and pride demands I stand tall and live out the destiny that the Gods have bestowed upon me!" Fine words that get replaced by "I am only a useless drunken indian......i have no future...must live in white mans world. Build plenty big casino and get drunk all day long." Thats quite a conflict. >>>> 2. The studies of Young et al. which have identified the > locations of >> specific genes on human chromosomes that relate to myopia > development. Yes moron. The locations have been identified. It's just the specific genes, meaning their reading frame, promoter sites, exact mutations, function of the encoded protein, etc. that remain unclear. Your understanding of molecular biology/molecular genetics is zero. >> The fact that specific chromosomal loci are known that segregate > completely [quoted text clipped - 5 lines] > an **unusual** rapid onset myopia commonly observed in the young and > different to common school myopia So, it's only now that you are trying to make this distinction. In your exasperated postings from last night you stated: "Still no evidence of myopia being genetic" and "Maybe i should offer a significant cash price to whoever can come up with any evidence at all its genetic??" Now you seek to recognize that there are two types of myopia (Doo..) and that while you now must admit that one of them is indeed clearly genetic, you still want to fight over the other type. Sorry, but you lose on that one too. There is good data to suggest genetic influences on school myopia as has been presented to you ad nauseum by me and others. By the way, what is the cash prize you are offering? And as Dr. Judy stated, perhaps your statement needs to be rephrased " If anybody knows of any studies that suggest myopia is linked to anxiety and which demonstrates good science then I am very interested to read them" > Good grief. I want to understand. Its you who seem determined to > convert 'Loci' into 'specific gene' and exstrapolate unusual myopia to > common myopia No Andrew-- I am simply trying to explain to you the concepts of molecular genetics. I can only imagine that your continued claims that the genes don't exist and that there isn't evidence for them in the face of reading the articles themselves means that you really don't understand how gene mapping works. It's different from psychology. >>> And why do many tribes of American Indians have high astigmatism-- is > it that they ALL have conflicting messages from their parents? [quoted text clipped - 19 lines] > > Thats quite a conflict. I see. So those stereotypical influences cause astigmatism in Indians. What about those persons that have indian blood that never knew it? What about the more recent generations of Indians that are well acclimated into current society and don't "worry" about "white men", "drinking", and "great-god-in-sky". Do you believe they will cease to continue to have high levels of astigmatism? What about their children? I'll bet not. Just for fun, how would you propose to treat such stressed out persons? Do you think some counseling, tranquilizers, sitar music, and meditation will affect their refractive outcomes? Try it and publish your findings. > >>>> 2. The studies of Young et al. which have identified the > > locations of > >> specific genes on human chromosomes that relate to myopia > > development. > > Yes moron. The locations have been identified. A Moron is a short fat hairy dwarf found in certain areas of south america resulting from some thyroid problem or other. I am not sure how this is relevant to my ablity to read the studies you are quoting. In Youngs first 18P study (his mapped area is a big area rather than a locus as you want to believe) he had 8 families. Some mapped to 18P and some did not In Youngs second 12 Q study he used one large italian German family only. "Familial high myopia 1.7-2.1% of population" Young TL, Ronan SM, Drahozal LA, Wildenberg SC, Alvear AB, Oetting WS, et al. Evidence that a locus for familial high myopia maps to chromosome 18p. Am J Hum Genet 1998; 63: 109-119 Young TL, Ronan SM, Alvear AB, Wildenberg SC, Oetting WS, Attwood LD, et al. A second locus for familial high myopia maps to chromosome 12q. Am J Hum Genet 1998; 63: 1419-1424[CrossRef][ISI][Medline]. Other studies show no evidence his study is applicable to other myopes "common myopia or school myopia" http://www.biomedcentral.com/1471-2350/5/20 Conclusions Significant evidence of linkage (LOD> 3) of myopia was not found on chromosome 18p or 12q loci in these families. These results suggest that these loci do not play a major role in the causation of common myopia in our families studied. Lets just stick to facts if you do not mind. > > Yes moron. The locations have been identified. > > A Moron is a short fat hairy dwarf Actually I was wrong here. For some reason i got confused with a cretin. andrewedwardjudd@hotmail.com wrote in news:1111136031.814892.272650 @o13g2000cwo.googlegroups.com: >> > Yes moron. The locations have been identified. >> [quoted text clipped - 3 lines] > > For some reason i got confused with a cretin. Do you often get confused with a cretin? How surprising Scott Again, you confuse high pathological myopia with common school myopia. The gene mapping studies are focused on high pathological myopia because it is so prevalent in certain families (meaning genetic.... doo..). There results admittedly say nothing about common school myopia (nobody here ever claimed anything different) although they do demonstrate that genetics CAN POTENTIALLY play a role in other types of myopia also. For example Andrew, do you understand the role of genetics in breast cancer? ================ > Conclusions > [quoted text clipped - 4 lines] > > Lets just stick to facts if you do not mind. > Again, you confuse high pathological myopia with common school myopia. The > gene mapping studies are focused on high pathological myopia because it is > so prevalent in certain families (meaning genetic.... doo..). There results > admittedly say nothing about common school myopia (nobody here ever claimed > anything different) although they do demonstrate that genetics CAN > POTENTIALLY play a role in other types of myopia also. I find it interesting that some people seem so determined to say that things that are observed in families are genetic in origin. Adolf Hitler was fond of that sort of thing. Many of these high myopia studies are using Jewish families or Armish families. Adolf would be delighted to know that these people are so easily regarded as being genetically defective. Terri Young looked at 8 families and found evidence in some of them the trait was linked to 18P. She then looked at one other large family and found evidence in some of them the trait was linked to 12Q Other researchers have looked at other similarly small numbers of people in families and said no evidience for 18P or 12Q but evidence in some of them for the 'long arm of 17' What exactly are they finding here? Genes for bushy eyebrows or curly eyelashes? Maybe its a gene for a desire to wear a skull cap? Meanwhile another Jew, Roberto Kaplan OD says that the behavioural factors are whats creating the family relationships. In the final analysis I have not found evidence that Terri Youngs familial high myopia is any different to school myopia. Familial high myopia appears to be just another common myopia. "High myopia is not sudden onset. It just starts early (e.g. age 6-8 years) and continues until adulthood." You guys can huff and puff all you want but meanwhile this remains a highly controversial area where belief seems more important than any facts that are currently available. If you do find any red hot evidence I am sure you would want me to read it. Where is it????????????? |
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