Branchio-oculo-facial syndrome

Branchio-oculo-facial syndrome (BOFS) is a rare genetic disorder characterized by a wide spectrum of abnormalities affecting primarily the branchial arches, eyes, and face. The syndrome is inherited in an autosomal dominant pattern, meaning a single copy of the altered gene in each cell is sufficient to cause the disorder. The gene associated with BOFS is TFAP2A, located on chromosome 6.

Symptoms

The clinical presentation of BOFS can vary significantly among affected individuals. Common features include:

• Branchial anomalies: These may include skin tags, sinus tracts, or cysts near the neck or collarbone, derived from the developmental remnants of the branchial arches.
• Ocular abnormalities: Individuals with BOFS may have microphthalmia (abnormally small eyes), coloboma (a defect in the eye, where normal tissue in or around the eye is missing), or strabismus (crossed eyes).
• Facial features: Distinctive facial characteristics can include a small lower jaw (micrognathia), cleft lip and/or palate, and distinctive ear shape or structure.

Additional features may involve the heart, kidneys, and ears, including hearing loss. Intellectual development is typically normal, but some individuals may have learning disabilities.

Diagnosis

Diagnosis of BOFS is primarily based on clinical evaluation and the presence of characteristic features. Genetic testing for mutations in the TFAP2A gene can confirm the diagnosis. Prenatal testing may be available for families with a known mutation.

Treatment

There is no cure for BOFS, and treatment is symptomatic and supportive. Management may involve a multidisciplinary team including specialists in genetics, ophthalmology, dermatology, otolaryngology, and plastic surgery. Surgical interventions may be necessary for cleft lip and/or palate, branchial cleft anomalies, and to correct some of the ocular and ear abnormalities. Regular monitoring and management of hearing, vision, and kidney function are important.

Epidemiology

BOFS is a very rare disorder, with a small number of cases reported in the medical literature. The exact prevalence is unknown.

Genetics

The TFAP2A gene provides instructions for making a protein that plays a crucial role in the development of the facial features, skin, and nervous system. Mutations in this gene disrupt the normal development of these structures, leading to the features of BOFS. The inheritance pattern is autosomal dominant.

See Also

• Genetic disorder
• Cleft lip and palate
• Coloboma
• Microphthalmia