title: Single nucleotide polymorphisms and haplotypes analysis of DFNB1 locus in Chinese sporadic hearing impairment population.
abstract: BACKGROUND
  The DFNB1 locus, which contains the gap junction beta-2 (GJB2) and gap junction beta-6 (GJB6) genes, plays a key role in the nonsyndromic and sporadic hearing impairment. Mutations of DFNB1 result in autosomal recessive nonsyndromic hearing impairment (ARNSHI). Previous researches have identified mutations in GJB2 and GJB6, but single nucleotide polymorphisms (SNPs) of DFNB1 locus have not been studied. So we chose five SNPs to evaluate whether there is difference between deafness people and normal-hearing people in Han Chinese.
  
  
  METHODS
  Five SNPs in the DFNB1 region were examined using a case-control association study between cases with sporadic hearing impairment and controls with normal hearing. The HWEsoft and SHEsis softwares were used to analyze the results.
  
  
  RESULTS
  Single-locus association analysis showed a positive association for three SNPs: rs9315400, rs2274084 and 235delC. When we compared the distributions of the haplotypes, we also found significant differences between cases and controls in the haplotype combination of rs2274084 and rs2274083 (chi(2) = 12.978, df = 3, global P = 0.004719).
  
  
  CONCLUSIONS
  The haplotypes composed of rs2274084 and rs2274083 suggested that C-C may be a risk haplotype for the sporadic hearing impairment while T-T may be protective against hearing impairment. From that point of view, we can conclude that the SNPs of DFNB1 locus also plays an important role in sporadic hearing impairment cases.
authors.affiliation: Department of Biotechnology, Nanjing Medical University, Nanjing, Jiangsu 210029, China.
authors.forename: Hong-bo
authors.initials: HB
authors.lastname: Cheng
authors.forename: Zhi-bin
authors.initials: ZB
authors.lastname: Chen
authors.forename: Qing-jun
authors.initials: QJ
authors.lastname: Wei
authors.forename: Ya-jie
authors.initials: YJ
authors.lastname: Lu
authors.forename: Guang-qian
authors.initials: GQ
authors.lastname: Xing
authors.forename: Xin
authors.initials: X
authors.lastname: Cao
mesh_terms: D000293:Adolescent; D002648:Child; D000072259:Connexin 26; D000075302:Connexin 30; D017630:Connexins / Q000235:genetics*; D005260:Female; D006239:Haplotypes; D034381:Hearing Loss / Q000235:genetics*; D006801:Humans; D008297:Male; D020641:Polymorphism, Single Nucleotide
chemical_list: D000075302:Connexin 30; D017630:Connexins; C000607042:GJB2 protein, human; C491020:GJB6 protein, human; D000072259:Connexin 26