SNP Shot: Genomic Insights

Craniofacial-deafness-hand syndrome is defined by a specific set of traits: noticeable facial characteristics, significant hearing impairment, and unusual hand structures.

The unique facial appearance in individuals with craniofacial-deafness-hand syndrome stems from various developmental issues affecting the skull and face. Common features include underdeveloped or missing nasal bones, leading to a small nose, thin nostrils, a flattened midface, and a flat nasal bridge. They also typically present with widely spaced eyes (ocular hypertelorism), narrow eye openings (narrowed palpebral fissures), an underdeveloped upper jaw (hypoplastic maxilla), and a small mouth with pursed lips.

Profound, congenital (present at birth) hearing loss due to inner ear abnormalities (sensorineural deafness) is also a hallmark of this condition.

Hand abnormalities in affected individuals often include ulnar deviation, where all fingers angle outwards towards the little finger. Additionally, permanently bent third, fourth, and fifth fingers (camptodactyly) are common, which can restrict finger movement and result in joint contractures. Wrist contractures can further restrict hand function.

Inheritance:

Craniofacial-deafness-hand syndrome follows an autosomal dominant inheritance pattern. This means that only one copy of the mutated gene is needed in each cell to cause the syndrome.