Hap Map Project - Bgbunict.it

Much of what was previously known about the role of CNVs in disease
comes from a rich literature on ‘genomic disorders’.
Genomic disorders are defined as a diverse group of genetic diseases that
are each caused by an alteration in DNA copy number.
These mutations can be relatively large, microscopically visible
imbalances, such as in Prader-Willi syndrome, or they may be much
smaller, requiring higher resolution detection methods, such as in Williams
Syndrome.
Genomic disorders are typically sporadic in nature because the CNV in
most cases is a de novo mutation with nearly complete penetrance, and
because the affected individuals have severe developmental problems and
are unlikely to have offspring.
However, there are notable examples of mendelian disease traits
associated with CNVs. For example, duplications of the gene for peripheral
myelin protein 22 (PMP22) cause the dominant neuropathy Charcot-Marie
Tooth disease type 1A, and deletions of the α-globin gene cluster cause
the recessive anemia α-thalassemia.