Objective: To establish a low-cost, convenient and accurate multiplex quantitative ligase chain reaction (MQ-LCR) technique to detect the five common mutations in Chinese patients with deafness.
Methods: Primers and probes for 5 common mutations of deafness genes, i.e., GJB2 gene 235delC and 299-300delAT, mtDNA A1555G, SLC26A4 gene IVS7-2 A>G and 2168A>G, were designed and synthesized. The technique for those mutations was established, and the reliability of the technique was tested in 98 patients with impaired hearing and 30 children with normal hearing, who were randomly selected from the ENT in Children's Hospital of Fudan University. The subjects were detected by MQ-LCR and direct DNA sequencing of PCR products, following a double-blind approach. Finally the results from the two methods were compared.
Results: The results revealed 48 cases carried two mutations, 31 cases carried heterozygous mutations in the 98 deaf children, and 3 had heterozygous mutation in 30 normal controls. These results were consistent with that from DNA sequencing. No false positive and false negative result was obtained.
Conclusion: The MQ-LCR technique established in this study is of low-cost, convenience, accuracy, high sensitivity and high specificity. It is suitable for large-scale detection and preventive diagnosis of mutations in deafness.