OBJECTIVE: To determine the frequencies of deafness gene mutations among patients with non-syndromic hearing loss (NSHL) from northern Jiangsu province. METHODS: A total of 117 patients with NSHL were enrolled. The coding region of GJB2 gene, IVS7-2A>G and 2168A>G mutations of SLC26A4 gene, and 1555A>G and 1494C>T mutations of mitochondrial DNA 12S rRNA were subjected to Sanger sequencing. Patients in whom no mutation was detected were further tested by targeted gene capture and high-throughput sequencing. RESULTS: Among the 117 patients, 86 (73.50%) were found to carry mutations. GJB2 gene mutations were found in 61 patients (52.14%), including 22 (18.80%) with homozygous mutations and 39 (33.33%) with heterozygous mutations. SLC26A4 gene mutations were found in 19 patients (16.24%), including 4 (3.42%) with homozygous mutations and 15 with heterozygous mutations (14.53%). Mitochondrial 12S rRNA gene mutation was found in 6 patients (5.13%). Targeted gene capture and high-throughput sequencing of 8 patients identified 4 further cases, including 1 with RDX gene 129_130del and 76_79del compound heterozygous mutations, 1 with OTOF gene 1274G>C homozygous mutation, 1 with SLC26A4 gene 919-2A>G and IVS16-6G>A compound heterozygous mutation, and 1 with SLC26A4 gene 919-2A>G and A1673T compound heterozygous mutation. CONCLUSION The frequency of mutation among patients with NSHL from north Jiangsu was 73.50%, and GJB2 gene was most commonly mutated.
China ; Connexins ; DNA Mutational Analysis ; DNA, Mitochondrial ; Hearing Loss ; genetics ; Humans ; Membrane Proteins ; Mutation ; Sulfate Transporters

Objective To evaluate the risk factors and sonographic findings of pregnancies complicated by placenta increta or placenta percreta. Methods Totally, 2219 cases were retrospectively analyzed from 20 tertiary hospitals in China from January 2011 to December 2015. The data were collected based on the original case records. All cases were divided into two groups, the placenta increta (PI) group (79.1％, 1755/2219) and the placenta percreta (PP) group (20.9％, 464/2219), according to the degree of placental implantation. The risk factors and sonographic findings of placenta increta or percreta were analyzed by uni-factor and logistic regression statistic methods. Results The risk factors associated with the degree of placental implantation were age, gravida, previous abortion or miscarriage, previous cesarean sections, and placenta previa (all P<0.05), especially, previous cesarean sections (χ2=157.961) and placenta previa (χ2=91.759). Sonographic findings could be used to predict the degree of placental invasion especially the boundaries between placenta and uterine serosa, the boundary between placenta and myometrium, the disruption of the placental-uterine wall interface and loss of the normal retroplacental hypoechoic zone(all P<0.01). Conclusions Previous cesarean sections and placenta previa are the main independent risk factors associated with the degree of placenta implantation. Ultrasound could be used to make a prenatal suggestive diagnosis of placenta accreta spectrum disorders.