molecular genetics of the complex multifactorial diseases

Unravelling the molecular genetics of the complex
multifactorial diseases is much more difficult than for single
gene disorders. Nevertheless, this is an important task as these
diseases account for the great majority of morbidity and
mortality in developed countries. Approaches to multifactorial
disorders include the identification of disease associations in
the general population, linkage analysis in affected families,
and the study of animal models. Identification of genes causing
the familial cases of diseases that are usually sporadic, such as
Alzheimer disease and motor neurone disease, may give
insights into the pathogenesis of the more common sporadic
forms of the disease. In the future, understanding genetic
susceptibility may enable screening for, and prevention of,
common diseases as well as identifying people likely to respond
to particular drug regimes.