Novel Mutation of DLC1 in Familial Cleft Palate

Objectives: Cleft palate is one of the most frequent congenital craniofacial disorder. It is well known that cleft palate is a multi-factorial disease which is influenced by both genetic and environmental factors.
Methods: In this study, we performed exome sequencing in multiple familial cleft palate case in order to find gene mutation which contribute to CLP phenotype.
Results: From this analysis, we discovered novel single nucleotide mutation which causes amino acid transition in DLC1 (Deleted in Liver Cancer 1) in two independent families. DLC1 is one of the member of Rho kinase family and consists with multiple isoforms and the mutation located in isoform 5 specific exon1. In situ hybridization revealed the expression of DLC1 isoform 5 in developing palatal shelves. Furthermore, CHIP seq analysis with cranial neural crest cells showed accumulation of TFAP2A, at possible regulatory region of DLC1 with P300. We also generated a mouse model carrying the same mutation using genome editing technique. Among these mice, we discovered cleft palate phenotype in one of these F1 generation heterozygous newborn pups.
Conclusions: From these results, we hypothesize this novel DLC1 mutation contribute to the pathogenesis of cleft palate in human.