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Objective To explore the genetic pathogen of patients with non-syndromic hearing impairment and to provide prenatal diagnosis for the families of hereditary deafness. Methods Mutation screening of GJB2, SLC26A4, GJB3 and mitochondrial 12 S rRNA genes was performed in 208 patients with non-syndromic hearing impairment by gene chip. Then direct sequencing was used in 41 patients who were found one mutation of GJB2 or SLC26A4 gene. And prenatal diagnosis was carried out in two families by direct sequencing. Results Eighty-six patients (41.35％) were found at least one mutation by gene chip. Among them, 40 patients were found to carry two mutations and 46 patients were found to carry one mutation. The most frequent mutation was 235delC, which was found in 46 patients. And 12 cases were found the second mutation through direct sequencing. A total of 52 (25.00％) patients were detected two mutations. Prenatal diagnosis showed that one fetus carried compound mutations of 299-300delAT and 235delC, and another one carried heterozygous mutation of IVS7-2A>G. Conclusion Patients with non-syndromic hearing impairment can be accurately diagnosed by gene chip and Sanger sequencing. The prenatal diagnosis is primary means for high-risk fetuses.
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<p><b>OBJECTIVE</b>To compare villus cell culture and karyotype analysis with single nucleotide polymorphism (SNP) microarray technology for the detection of chorionic villus chromosome in patients with retention of abortion.</p><p><b>METHODS</b>Forty cases were analyzed with the two methods.</p><p><b>RESULTS</b>Chorionic villus culturing was successful in 29 cases, among which 10 were found to have an abnormal karyotypes. For the SNP microarray analysis, all 40 cases were successful, among which 16 were shown to have an abnormal molecular karyotype.</p><p><b>CONCLUSION</b>SNP microarray technology is highly accurate and specific, which is particularly suitable for the detection of chromosomal deletions or duplications, uniparental disomy, low-percentage mosaicism and other chromosomal abnormalities. It has provided an effective supplement to the conventional chorionic villus culture and karyotype analysis.</p>