A novel mutation in COL1A1 causing osteogenesis imperfecta/hearing loss

Area of Science:

• Genetics and Molecular Biology
• Otolaryngology
• Orthopedics

Background:

• Osteogenesis imperfecta (OI) is a genetic disorder characterized by brittle bones and often associated with hearing loss.
• Identifying specific gene mutations is crucial for understanding OI pathogenesis and associated symptoms.
• Hearing loss in OI patients can significantly impact quality of life.

Purpose of the Study:

• To identify mutations in COL1A1 and COL1A2 genes in a family with type I osteogenesis imperfecta and hearing loss.
• To analyze the characteristics and recovery of hearing loss in patients with osteogenesis imperfecta.
• To evaluate the efficacy of stapedial surgery for hearing loss in OI patients.

Main Methods:

• Clinical data collection from OI proband and parents.
• Peripheral blood sample analysis using PCR amplification and Sanger sequencing for COL1A1 and COL1A2 genes.
• Literature review on stapedial surgery outcomes in osteogenesis imperfecta patients.

Main Results:

• A heterozygous mutation (c.1922_1923 ins C) in exon 26 of the COL1A1 gene was identified in the OI proband, causing a p.Pro 601FS frameshift mutation.
• A homozygous mutation (c.1782>G) in exon 28 of COL1A2 was detected in both the proband and her parents, leading to a p.Pro 549Ala protein change.
• Literature suggests stapedial surgery can offer hearing benefits to OI patients.

Conclusions:

• The proband's OI symptoms are attributed to the heterozygous COL1A1 gene mutation.
• Stapedial surgery is a viable option for managing hearing loss in osteogenesis imperfecta, providing both short-term and long-term benefits.