Family History of Nonsyndromic Orofacial Clefts: A Brazilian Multicenter Study

To summarize the evidence on the relationship between hereditary family history and nonsyndromic orofacial clefts (NSOC) in patients from various Brazilian states. This cross-sectional multicenter study was conducted at six specialized orofacial cleft services across different regions of Brazil. The sample consisted of 1899 patients with NSOC, including cleft lip only (NSCLO), cleft palate only (NSCPO), and cleft lip and palate (NSCLP). Data were collected from clinical records between June 2023 and May 2024. Family history was classified as positive or negative, with additional details on the number of affected relatives, degree of kinship, and type of oral cleft. Statistical analysis was performed using SPSS version 27.0, with chi-square tests and z tests to assess associations between variables, and Student's t test to compare the mean number of affected relatives among cleft types. Of 1899 patients, 52.6% had NSCLP, 24.11% had NSCPO, and 23.27% had NSCLO. NSCLP and NSCLO were more common in males, while NSCPO was more frequent in females. NSCLP and NSCLO showed similar rates of positive family history, whereas NSCPO had significantly fewer cases with hereditary links. Third-degree relatives were the most affected across all groups. NSCLP and NSCLO showed a higher frequency in males and more cases of positive family history compared to NSCPO. Further studies are needed to explore the genetic basis of NSOC, particularly in genetically diverse populations like Brazil.