Genome-wide copy number scan identifies IRF6 involvement in Van der Woude syndrome in an Indian family.

Summary Van der Woude syndrome (VWS) is an autosomal dominant developmental malformation presenting with bilateral lower lip pits related to cleft lip, cleft palate and other malformations. We performed a whole-genome copy number variations (CNVs) scan in an Indian family with members suffering from VWS using 2·6 million combined SNP and CNV markers. We found CNVs affecting IRF6, a known candidate gene for VWS, in all three cases, while none of the non-VWS members showed any CNVs in the IRF6 region. The duplications and deletions of the chromosomal critical region in 1q32-q41 confirm the involvement of CNVs in IRF6 in South Indian VWS patients. Molecular network analysis of these and other cleft lip/palate related module genes suggests that they are associated with cytokine-mediated signalling pathways and response to interferon-gamma mediated signalling pathways. This is a maiden study indicating the involvement of CNVs in IRF6 in causing VWS in the Indian population.