First reported CABP2-related non-syndromic hearing loss in Northern Europe

Area of Science:

• Genetics
• Otolaryngology
• Human Molecular Genetics

Background:

• Calcium-binding protein 2 (CABP2)-related non-syndromic hearing loss is rare, with previous cases documented primarily in Middle Eastern and South Asian families.
• The condition typically presents as prelingual, symmetrical, moderate-to-severe hearing loss.

Observation:

• A novel case of CABP2-related autosomal recessive hearing loss is identified in an 8-year-old Danish Caucasian boy.
• The individual is homozygous for the splice site variant c.637+1G>T in the CABP2 gene, previously reported in Iranian and Pakistani families.

Findings:

• This represents the first documented instance of CABP2-related hearing loss in Northern Europe.
• While the parents are not consanguineous, loss of heterozygosity in a chromosomal region encompassing CABP2 suggests a shared ancestral origin.

Implications:

• This finding expands the geographical spectrum of CABP2-related hearing loss.
• It highlights the importance of considering genetic testing for hearing loss in diverse populations.
• Further research may elucidate the prevalence and specific genetic factors contributing to hearing loss in Northern European populations.