Objective: To explore the genetic basis for a patient with syndromic hearing loss.
Methods: Genomic DNA of the patient was extracted, for which 127 deafness-related genes were enriched with a chip. Following next generation sequencing, pathogenic loci in exonic regions were analyzed through comparison against the databases. Genotype of her fetus for the suspected site was determined by testing the amniotic fluid sample. qPCR method was applied to verify the deletion of a large fragment.
Results: The proband was diagnosed with Waardenburg syndrome type 2, and had harbored a novel heterozygous deletion of the exons 3 and 4 of the SOX10 gene. Her fetus was found to carry the same deletion and presented with blue eyes and deafness after birth.
Conclusion: Waardenburg syndrome type 2 due to SOX10 gene deletion may feature autosomal dominant inheritance with incomplete penetrance. The deletion of exons 3 and 4 of the SOX10 gene probably underlies the disease in this family.