Endofenotypen in de psychiatrie: een tussenstand

- Inheritance plays an undisputedly important role in the development of most psychiatric disorders. However, the genes involved have mostly not yet been identified. In all probability, not a single gene but a large number of genes are involved in each disorder.

- In psychiatry, a lot is expected from research into the relationship between so-called endophenotypes and genotypes because endophenotypes are more closely related to the genotype and are better defined and quantifiable than the phenotype.

- Endophenotypes are biological or neuropsychological markers which are (a) associated with the disorder in the population, (b) are themselves heritable, (c) are manifest in the absence of the disorder, (d) cosegregate with the illness in the families and (e) are more prevalent in relatives of people suffering from the disease than in the general population.

- To date only a few markers have been examined in sufficient detail to know whether they fulfil these criteria. Therefore it is still too early to evaluate the significance of endophenotypes in psychiatry.

Ned Tijdschr Geneeskd. 2008;152:1911-3