Disease

Brief Summary

Van der Woude syndrome, also known as Lip-pit syndrome, is a disorder that affects facial development. It is a rare disease in which the cleft lip, cleft palate, or both are common in patients with this disease. The presence of salivary and mucous glands in the pits might make them appear moist. Small tissue lumps on the lower lip are also possible. Patients sometimes have missing teeth.

Source

Image:

Child with Van der Woude syndrome

Frequency

It occurs approximately 1 in 50 people. But, data from Europe and Asia suggests 1 in 35,000 to 1 in 100,000 individuals.

Inheritance

Van der Woude syndrome is inherited in an autosomal dominant manner.

History of the disease

In 1987, Bocian and Walker described a patient that had an interstitial deletion of chromosome 1q, del(1q32-q41). The patient was observed to have congenital lower lip pits that were found

in association with both van der Woude and popliteal pterygium syndrome. It was hypothesized that van der Woude syndrome is due to a submicroscopic deletion of chromosome 1q. Based on the report, a tentative assignment of the locus, symbolized PIT, to 1q32-q41 was made.

Brief Summary

VAN DER WOUDE SYNDROME

Pathogenesis

Over 70% of patients with VWS have mutations in the IRF6 gene (1q32.2-q32.3), which is involved in epidermal development and craniofacial development regulation.IRF6 mutations are also responsible for popliteal pterygium syndrome. Whole-gene deletions are a very rare cause of VWS, and the frequency of partial-gene deletions is unknown. Eight families with VWS were recently revealed to have mutations in the gene GRHL3 (1p36), which codes for a Grainyhead-like protein 3 homolog, but no causal mutations in IRF6.

Pathogenesis

Source

Image:

Dominant mutations on GRHL3 disrupt oral development

Symptoms

Small mounds of tissue on their lower lip.

A gap in their lip (cleft lip).

An opening in the roof of their mouth (cleft palate).

Pits near the center of their lower lip

Social Concerns

Van der Woude syndrome is an autosomal dominant pattern that only requires the presence of one altered gene to give rise to this condition. In a pregnancy, there is a 50 percent chance of the offspring inheriting this condition if the Van der Woude syndrome is already present within the family, especially in the parent. Within the course of an individual’s development, the aid of professionals may be required to oversee the needs of surgery and dental concerns. Due to facial abnormalities, there is a heightened risk of delayed language development and other cognitive disabilities. However, this does not greatly affect the IQ of individuals with this condition.

Treatment

For individuals with cleft lip and/or cleft palate, surgery may be requested to repair the cleft although it is not required. Some patients may be eligible for excision of the lip sinus tracts in the case of recurrent inflammation. In addition to preventing the formation of a mucoid cyst, an excision of the sinus tract should be performed. Monitoring may also be required for possible language delays, speech problems, and learning disabilities. However, IQ does not significantly differentiate from the general population.

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