SNP Shot: Genomic Insights

Björnstad syndrome is an uncommon genetic condition distinguished by unusual hair and hearing issues. Individuals with this syndrome exhibit pili torti, a condition where the hair shafts appear twisted when examined microscopically, hence the name "twisted hair." The hair is fragile, prone to breakage, resulting in short, slow-growing hair. In Björnstad syndrome, pili torti typically only impacts the scalp hair; the eyebrows, eyelashes, and body hair remain unaffected. The extent of hair involvement and the severity of fragility and breakage can differ among affected individuals. This hair abnormality usually manifests before age 2 and may lessen in severity as the individual gets older, especially after puberty.

Individuals with Björnstad syndrome also experience hearing impairments that become noticeable during early childhood. This hearing loss, caused by sensorineural deafness (inner ear abnormalities), can vary from mild to profound. Those with mild hearing loss may struggle to hear certain frequencies, while those with severe hearing loss may have no hearing ability.

Inheritance:

Björnstad syndrome follows an autosomal recessive inheritance pattern. This signifies that both copies of the responsible gene within each cell must carry a mutation for the condition to manifest. The parents of a person with an autosomal recessive disorder each carry one copy of the mutated gene, but they usually do not display any signs or symptoms of the condition themselves.