The genetics and epigenetics of orofacial clefts.

Orofacial clefts (cleft lip, cleft palate) are among the most common of all major birth defects, but very little is known about their causation. Genetic factors are thought to play a major role, and there has been considerable recent effort to map and identify genes that constitute risk factors for clefts. This review will put into perspective the frequently-conflicting results of these studies.