Forkhead genes and human disease.

Forkhead, or Fox-box genes, code for winged helix transcription factors that make up a multi-gene family. Two human genetic diseases have recently been associated with loss of function of one allele of different Fox-box genes: Axenfeld-Rieger anomaly of the anterior eye chamber associated with haploinsufficiency of FOXC1 and lymphedema-distichiasis associated with haploinsufficiency of FOXC2. Earlier, both genes had been studied intensively for their transcription patterns and for the phenotypes of knockouts. These studies are reviewed and related to the phenotypes found in the two human disorders.