GENETICS OF NONSYNDROMIC ORAL CLEFTS REVISITED

Nonsyndromic oral clefts are among the most common birth defects, affe cting approximately 1 in 1000 Caucasian newborns, In recent decades, m any investigators have used genetic and epidemiologic methods to ident ify etiologic factors, but results have often been inconclusive or con tradictory, Etiologic heterogeneity is undoubtedly a major component i n these birth defects, and there may not be a single answer to this pr oblem, Here, we describe the main features of published studies pointi ng out their strengths and limitations, Additionally, we give insight into current methods for detecting the presence of interaction between genetic markers and environmental exposures in the etiology of oral c lefts.