ABSTRACT
<p><b>OBJECTIVE</b>To map the gene responsible for nonsyndromic hearing impairment in a consanguineous family.</p><p><b>METHODS</b>Firstly, X chromosome scanning was used to exclude X chromosome. Secondly, candidate gene analyzing and genome scanning were performed by homozygosity mapping. Then, additional markers flanking the tightly linked marker were tested to confirm linkage and decide the candidate region.</p><p><b>RESULTS</b>The nonsyndromic hearing impairment of this family was autosomal recessive. Twenty-five known genes were excluded. Autosomal genome scanning indicated that D17S1293 was tightly linked with disease gene. And further study mapped the disease gene to a 5.07 cM interval bounded by D17S1850 and D17S1818.</p><p><b>CONCLUSION</b>The disease gene of the family is mapped to a 5.07 cM interval between D17S1850 and D17S1818, which is a new locus of autosomal recessive nonsyndromic hearing impairment.</p>
Subject(s)
Female , Humans , Male , Chromosome Mapping , Methods , Chromosomes, Human, Pair 17 , Genetics , Chromosomes, Human, Pair 18 , Genetics , Chromosomes, Human, X , Genetics , Consanguinity , Family Health , Genetic Predisposition to Disease , Genetics , Hearing Loss, Sensorineural , Genetics , Microsatellite Repeats , PedigreeABSTRACT
<p><b>OBJECTIVE</b>To study the prevalence of methylenetetrahydrofolate reductase (MTHFR) C677T genotype and its association with deep vei n thrombophilia in Chinese.</p><p><b>METHODS</b>Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was conducted to examine mutation with 63 deep vein thrombophilic patients and 80 health controls in Shandong Hans. The genotype frequencies were calculated by gene counting in patients and controls, and an analysis was made on the association of MTHFR C677T mutation with deep venous thrombosis in Shandong Hans.</p><p><b>RESULTS</b>In case- controls, the frequencies of C/T heterozygote were 41.27% and 43.75%; whereas those of T/T homozygote were 52.38% and 36.25%. Significantly elevated mutation was observed in patients(Chi-square=6.372, P 0.01 OR(T/T)=4.552 95% confidence interval:1.440-14.390, Chi-square =6.742 P=0.009).</p><p><b>CONCLUSION</b>The C677T mutation of methylenetetrahydrofolate reductase gene is a risk factor associated with deep vein thrombophilia in Shandong Hans.</p>