P793: Segregation of a nonsense variant in TP63 in a five-generation family with non-syndromic cleft lip and palate

A maternally inherited heterozygous stop gain variant, c.1177C>T (p.Arg393Ter), located in the oligomerization domain of the TP63 gene was identified and classified as likely pathogenic based on the ACMG/AMP variant guidelines. Targeted analysis of several maternal relatives indicates segregation of the variant with the maternal grandmother, who was born with cleft lip and palate, as well as the mother, aunt, and uncle, who did not have cleft lip or cleft palate, consistent with incomplete penetrance.