As medical researchers unlock the secrets of the human genome,
they are learning that nearly all diseases have a genetic
component. Some are caused by a mutation in a gene or group of
genes. Such mutations can occur randomly or due to an
environmental exposure. Other disorders are hereditary. These
can be passed down from generation to generation within a
family. Finally, many-perhaps most-genetic disorders are caused
by a combination of small variations in genes operating in
concert with environmental factors. Genetic Disorders
Sourcebook, Fourth Edition offers information on how genes work,
and it provides facts about the most common genetic disorders,
including those that arise from mutations in specific genes,
those that arise from chromosomal abnormalities, and disorders
with genetic and environmental components, such as cancer,
diabetes, mental illness, obesity, and addiction. Reports on
current research initiatives describe the newest breakthroughs
in the causes and treatments of genetic disorders, gen