Defining Predictors of Cleft Lip and Palate Risk

Individuals with clefts present considerably more dental anomalies than individuals without clefts. We also have shown that these individuals report cancer in their families more often than do unaffected individuals. We investigated how these conditions correlated with genetic variants associated with clefts to ascertain if specific molecular signatures exist that could help identify individuals at risk for having offspring with these defects. We examined 573 individuals, 158 with clefts, 254 unaffected family members, and 161 non-related controls. Several clinical features, such as laterality, the presence of dental anomalies, medical history, and pregnancy history, were used to assess each individual's cleft status. Then, we performed molecular studies with genes that have been independently associated with oral clefts. We analyzed two datasets: nuclear families and case-control individuals where the case was the child from the family and controls were unrelated non-clefted individuals. In the family data, we confirmed association between clefts and rs987525 on chromosome 8 (p = 0.007) and found an association with rs987525 and tooth agenesis (p = 0.0003). In the case-control data, clefts, supernumerary teeth and familial cancer history were associated with ABCA4-rs481931 on chromosome 1 (p = 2E-19, 0.0007, 2E-06, respectively), and clefts and microdontia were associated with rs1325474 on chromosome 6 (p = 1E-06, 0.0002, respectively).