Feingold syndrome

Feingold syndrome (also known as microcephaly‑mesobrachyphalangy‑tracheoesophageal fistula (MMT) syndrome, microcephaly‑oculo‑digito‑esophageal‑duodenal (MODED) syndrome, or oculo‑digito‑esophagoduodenal (ODED) syndrome) is a rare genetically determined congenital disorder; its incidence is unknown. It affects a wide range of tissues and organs. To date, it has been confirmed in only several dozen individuals worldwide. The syndrome is highly variable, with manifestations ranging from mild to severe. Even individuals within the same family may differ significantly.

Causes

The disorder is caused by a mutation in the MYCN gene, which is located on chromosome 2. This gene is responsible for the production of a protein that plays an important role in the formation of tissues and organs during embryonic development. Animal studies suggest that this protein is crucial for the normal development of the limbs, heart, kidneys, nervous system, digestive tract, and lungs.

The MYCN protein regulates the activity of other genes by binding to specific sites on DNA; therefore, it is classified as a transcription factor. The pattern of inheritance is autosomal dominant, meaning that only one altered gene inherited from one parent is sufficient for the disease to manifest.

Diagnosis

The diagnosis can be established by genetic testing, which demonstrates a mutation in the known and relevant gene.

Treatment

There is no prevention, and the syndrome cannot be cured. Tissue deformities may be addressed through plastic surgery, and obstructions of the gastrointestinal tract can be treated using conventional surgical methods. Intellectual disability may require comprehensive special education support and early intervention.

• deformities of the head, face, and limbs – the head may be abnormally small (microcephaly), the mandible may also be small (micrognathia), and the palpebral fissures are narrow
• some fingers may be short; the thumbs may be underdeveloped, and syndactyly (fusion of digits) may sometimes occur
• brachymesophalangia (congenital shortening of the middle phalanges) is present in almost all cases
• clinodactyly (malformation of the middle phalanx causing curvature of the finger)
• thumb hypoplasia (underdevelopment of the thumb)
• the gastrointestinal tract is also affected; congenital stenoses or atresia of the esophagus and small intestine are common, potentially obstructing the passage of food
• intellectual functioning is impaired; intellectual disability is usually present
• mild to severe learning difficulties
• less frequently, congenital defects of the heart and kidneys
• less common are hearing impairments of varying severity and growth abnormalities