Polygenic Disorders


The vast majority of common disorders affecting humans are polygenic, due to the additive and interactive effect of multiple genes, each with a small effect, interacting with the environment. Because of their importance and frequency, polygenic disorders have a great economic impact. The identification of the genes involved promises to be significantly more difficult than the identification of the genes involved in single gene disorders.

Keywords: polygenes; linkage disequilibrium; threshold models; microsatellites; single nucleotide polymorphisms; variance

Figure 1.

Threshold model of polygenic disorders.

Figure 2.

Example of a polygenic system (see text for details).

Figure 3.

Types of linkage disequilibrium (LD) (see text for details).



Comings DE (1996) Polygenetic inheritance of psychiatric disorders. In: Blum K, Noble EP, Sparks RS and Sheridan PJ (eds.) Handbook of Psychiatric Genetics, pp. 235–260. Boca Raton, FL: CRC Press

Comings DE (1998a) Why different rules are required for polygenic inheritance: lessons from studies of the DRD2 gene. Alcohol 16: 61–70.

Comings DE (1998b) Polygenic inheritance and micro/minisatellites. Molecular Psychiatry 3: 21–31.

Daly MJ, Rioux JD, Schaffner SF, Hudson TJ and Lander ES (2001) High‐resolution haplotype structures in the human genome. Nature Genetics 29: 229–232.

Paquette J, Giannukakis N, Polychronakos C, Vafiadis P and Deal C (1998) The INS 5′ variable number of tandem repeats is associated with IGF2 expression in humans. Journal of Biological Chemistry 273: 14158–14164.

Pritchard JK (2001) Are rare variants responsible for susceptibility to complex diseases? American Journal of Human Genetics 69: 124–137.

Risch NJ (2000) Searching for genetic determinants in the new millennium. Nature 405: 847–856.

Stern C (1973) Principles of Human Genetics, 3rd edn. San Francisco, CA: WH Freeman.

Strickberger MW (1968) Genetics. New York: Macmillan.

Contact Editor close
Submit a note to the editor about this article by filling in the form below.

* Required Field

How to Cite close
Comings, David E(Jan 2006) Polygenic Disorders. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1038/npg.els.0005556]