Surgical management of lower lip pits in Van der Woude syndrome

Causal Variations at IRF6 Gene Identified in Van der Woude Syndrome Pedigrees

The purpose of this study is to analyze the clinical characteristics of patients with Van der Woude syndrome (VWS) and to detect variations in each patient. Finally, the combination of genotype and phenotype can make a clear diagnosis of VWS patients with different phenotype penetrance.

Five Chinese VWS pedigree were enrolled. Whole exome sequencing of the proband was performed, and the potential pathogenic variation was further verified by Sanger sequencing in the patient and their parents. The human mutant IRF6 coding sequence was generated from the human full-length IRF6 plasmid by site-directed mutagenesis and cloned into the GV658 vector, RT-qPCR and Western blot were used to detect the expression of IRF6.

We found one de novo nonsense variation (p. Gln118Ter) and three novel missense variations (p. Gly301Glu, p. Gly267Ala, and p. Glu404Gly) co-segregated with VWS. RT-qPCR analysis revealed that p. Glu404Gly significantly reduced the expression level of IRF6 mRNA. Western blot of cell lysates confirmed that IRF6 p. Glu404Gly abundance levels were lower than those for IRF6 wild type.

This discovery of the novel variation (IRF6 p. Glu404Gly) expands the spectrum of known variations in VWS in Chinese humans. Genetic results combined with clinical phenotypes and differential diagnosis points from other diseases can make a definitive diagnosis and provide genetic counseling for families.

Lower lip pits with sinus tracts in Van der Woude syndrome: a case report and review of the literature

In Van der Woude syndrome (VWS), a rare congenital disease, lower lip pits (LLPs) can cause an aesthetically significant deformity. Surgical treatment of LLPs is necessary if they cause recurrent inflammation or aesthetic problems. Intraoperatively, surgeons should keep in mind the possibility of deep extension of the sinus tract and the relative deficiency of the midline in VWS, which increases the risk of lip disfigurement. Herein, we emphasize the importance of using a tissue-preserving technique to improve aesthetic results in VWS patients with a sinus tract.

Van der Woude Syndrome With a Novel Mutation in the IRF6 Gene

Van der Woude syndrome (VWS) is a rare autosomal dominant disease, first reported in the literature in 1845 by Demarquay and subsequently thoroughly described in 1954 by Van der Woude. Van der Woude Syndrome is the most common form of syndromic orofacial clefting and individuals with this syndrome account for 2% of all cleft cases. Van der Woude syndrome clinically presents with congenital lip pits. These lip pits occur on paramedian portion of the vermillion border of the lip. In VWS, congenital lip pits occur in concurrence with cleft lip and/or cleft palate and represent the most common clinical problem occurring in 80% of the patients. Lip pits result due to notching of the lips at an early stage of development with fixation of tissues at the base of the notch or they may result from a failure of complete union of embryonic lateral sulci of lip. Single lip sinuses without any cleft syndrome are rare; lower lip fistulas in VWS are generally asymptomatic, and surgical management is usually accomplished because of aesthetic concerns. However, in some cases, patients may complain of watery drainage or hypotonia of the lower lip. Herein, the authors report a novel frameshift mutation in IRF6 gene which may contribute to better understanding the genetic aspect of VWS.