Mutation analysis of seven patients with Waardenburg syndrome / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To perform genetic analysis for 7 patients with Waardenburg syndrome.</p><p><b>METHODS</b>Potential mutation of MITF, PAX3, SOX10 and SNAI2 genes was screened by polymerase chain reaction and direct sequencing. Functions of non-synonymous polymorphisms were predicted with PolyPhen2 software.</p><p><b>RESULTS</b>Seven mutations, including c.649-651delAGA (p.R217del), c.72delG (p.G24fs), c.185T>C (p.M62T), c.118C>T (p.Q40X), c.422T>C (p.L141P), c.640C>T (p.R214X) and c.28G>T(p.G43V), were detected in the patients. Among these, four mutations of the PAX3 gene (c.72delG, c.185T>C, c.118C>T and c.128G>T) and one SOX10 gene mutation (c.422T>C) were not reported previously. Three non-synonymous SNPs (c.185T>C, c.128G>T and c.422T>C) were predicted as harmful.</p><p><b>CONCLUSION</b>Genetic mutations have been detected in all patients with Waardenburg syndrome.</p>

Identification of novel common mutations among patients with non-syndromic hearing loss with high-throughput gene capture technology / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To identify novel common mutations among patients with non-syndromic hearing loss (NSHL).</p><p><b>METHODS</b>High-throughput gene capture technology was used to analyze 18 patients with NSHL in whom common mutations of deafness genes including GJB2, SLC26A4, GJB3, and mtDNA were excluded. Suspected mutation was verified with Sanger sequencing.</p><p><b>RESULTS</b>Next generation sequencing has identified 62 mutations in 29 genes associated with hearing loss, which included 54 missense mutations, 4 splicing mutations, 3 deletional mutations, and 1 nonsense mutation. Mutations occurring more than twice in the 18 patients were verified by Sanger sequencing. This has confirmed 15 mutations in 8 genes, including 3 missense mutations (p.C2184G, p.L2825P, p.H1888Y) which have not been reported previously. Meanwhile, p.L445W, p.D866N, and IVS919-2A>G were common causative mutations.</p><p><b>CONCLUSION</b>A number of common causative mutations, e.g., p.L445W, p.D866N, IVS919-2A>G, have been identified by high-throughput capture technology, which may facilitate the research and genetic diagnosis for hearing loss.</p>

Detection of common deafness-related genes among non-syndromic deafness patients from Shanxi province / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To explore the common causative genes and mutation sites for hereditary non-syndromic deafness in Shanxi.</p><p><b>METHODS</b>Peripheral blood samples were collected from regional schools for children with deafness. The samples were analyzed by matrix-assisted laser desorption ionization of flight mass spectrometry, and the results were verified by DNA sequencing.</p><p><b>RESULTS</b>For all samples, the 20 mutational sites of the 4 common causative genes were tested. As revealed, c.235delC of GJB2 gene has the highest mutational rate (13.67%). c.IVS7-2A>G of SLC26A (PDS) gene has a mutation rate of 17.67%, and c.1555A>G of mitochondrial 12S rRNA has a mutation rate of 2.00%. No mutations have been found with GJB3 gene. Sequencing analysis has suggested that the above results have a consistency rate of 99%.</p><p><b>CONCLUSION</b>Analysis of mutations of the 4 common deafness-related genes can facilitate early diagnosis and treatment for the disease. Matrix-assisted laser desorption ionization time of flight mass spectrometry is a reliable method for such a task.</p>