Family history in non-syndromic orofacial clefts: Is there a pattern?

OBJECTIVE: To survey the frequency and pattern of family history for non-syndromic orofacial clefts (NSOFC). Initial hypothesis: more complex forms have a higher frequency of positive family history. MATERIALS AND METHODS: A retrospective study was carried with 2,668 subjects with three different types of clefts (CL Group (cleft lip), CLP Group (cleft lip and palate), and CP group (cleft palate)); family history information was collected. The Chi-square (X(2) ) and Z-test were used. RESULTS: A positive family history was found in 31% of the sample. The CLP Group had highest percentage and highest proportion of affected relatives, being these factors statistically significant when compared to the CP Group. Comparisons between the CLP Male and CL Male with CP Male were statistically significant. First-degree kinship was the most frequently found. CONCLUSIONS: The initial hypothesis was confirmed, subjects with CLP had the highest percentage of positive family history, the highest proportion of affected relatives and had more affected relatives in comparison with CP. It is more common to find affected relatives in the CLP Male and CL Male groups when compared with CP Male. CLP and CP groups present a pattern of occurrence of the type of cleft in the family.