The prevalence, penetrance, and expressivity of etiologic IRF6 variants in orofacial clefts patients from sub-Saharan Africa.

This study demonstrates that exons 4 and 7 of IRF6 are mutational 'hotspots' in our cohort and that IRF6 mutants-induced orofacial clefts may be prevalent in the Africa population, however, with variable penetrance and expressivity. These observations are relevant for detection of high-risk families as well as genetic counseling. In conclusion, we have shown that there may be a need to combine both molecular and clinical evidence in the grouping of orofacial clefts into syndromic and nonsyndromic forms.