Sequence analysis of MPZ gene in a family with dominantly inherited auditory neuropathy

Objective:To investigate whether the MPZ gene contributes to the non-syndromic hearing loss of a Chinese pedigree with dominantly inherited auditory neuropathy(AN).Methods:Nine members in three generations of the family were selected for this study.Genomic DNA was isolated from the peripheral leukocytes of the patients using the Puregene DNA Isolation Kits.Firstly,the DNA fragment of the subjects was PCR amplified using oligonucleotides corresponding to exon 3 of the MPZ gene.Each fragment was purified and subsequently analyzed by direct sequencing in an Applied Biosystems 3730 automated DNA sequencer.The entire MPZ gene of one affected subject Ⅲ3 were then amplified with 6 overlapping fragments,and submitted for sequence analysis as described above.The resultant sequence data were compared with the standard sequence to identify deafness-associated mutations.Results:PCR amplifications were successfully conducted in all the subjects.We failed to detect the presence either mutations of Thr124Met and Tyr145Ser in the exon 3 that have been reported,or any other deafness-associated mutations in the whole MPZ gene,by sequence analysis.Conclusion:The MPZ gene seems not contribute to the pathogenesis of this Chinese AN family,which suggesting new gene(s) involvement.