I doubt VERY much if you have the background information needed to
start with a detailed book.  If you did have such skills you would not
need to have asked the question you asked.  Here is a web site that
starts with the basics and builds up to about the state of knowledge 25
or 35 years ago:

http://www.synapses.co.uk/genetics/index.html

Once you master this stuff you have some basis to tackle more recent
findings.  I am sure you can find all kinds of books at your local
public library that would be more then adequate to build your knowledge
base.  If the library does not happen to own the books they are usually
happy to get them on interlibrary loan at either no cost to you or very
minimal cost.

You do need to understand that to develop a detailed understanding of
the topic you are setting yourself a task just as difficult as some
high school age kid trying to teach himself advanced calc and
differential equations simply by reading books and self study.
Perfectly doable if you want to spend the many, many hours required.
Along the way you also need to learn a lot of chemistry and a lot of
statistics to understand the topic.

You also need to realize that we are just now learning how truly
devious evolution was in producing the whole genetic system.  Classic
mendelian genetics is proving to be hardly more then the tip of the
iceberg.  Perhaps in another 100 years we will actually have a decent
overall understanding.