Association between genotype and phenotype of virulence gene in Van der Woude syndrome families.

Members from two Van der Woude syndrome (VWS) families were screened to determine the prevalence of interferon regulatory factor 6 (IRF6) as a disease‑causing gene and to analyze the interrelationships between patient genotype and phenotype. The peripheral blood of 24 members from two VWS families and 200 control samples were collected. The family members were interviewed for medical histories and other clinical abnormalities using questionnaires. Polymerase chain reaction was directly performed on the peripheral blood to screen for the coding region of the IRF6 gene. Of the 24 family members, a total of 6 patients had mutations of IRF6 gene. c.1234C>T (p.R412X) heterozygous mutation was detected in 3 members of family 1. In families 2 and 3, members carried the c.1210G>A (p.E404K) heterozygous mutations. The other members of the families, were wild type (wt/wt) for IRF6. Genetic testing demonstrated that the disease mutations c.1234C>T and c.1210G>A co‑segregated with the two families' pathogenic mutations. The existence of genetic heterogeneity and the complexity of the clinical phenotype was demonstrated in Chinese VWS patients.