title: Association of rs1137101 polymorphism in LEPR and susceptibility to knee osteoarthritis in a Northwest Chinese Han population.
abstract: Osteoarthritis (OA) is a complex arthritic condition in which the genetic factor plays a crucial role. A single nucleotide polymorphism (SNP), rs1137101 (Gln223Arg) of leptin receptor (LEPR) gene has been demonstrated to be associated with susceptibility to knee OA. However, this association in Chinese Han population has never been examined. The present study aimed to investigate whether Gln223Arg was related to knee OA susceptibility in a Northwest Chinese population with Han ethnicity.
  
  
  
  Gln223Arg polymorphisms were genotyped in 587 patients with confirmed knee OA and in 628 age- and sex-matched healthy controls using polymerase chain reaction-restriction fragment length polymorphism analysis. Besides, LEPR genotypes were verified by direct DNA sequencing analysis on PCR products.
  
  
  
  The genotype and allele frequencies in LEPR SNP rs1137101 were significantly different between cases and control groups (chi-square = 6.52, P = 0.038 for genotype and chi-square = 5.06, P = 0.024 for allele frequencies; respectively). Rs1137101 was correlated with knee OA in the dominant genetic model (GG + GA versus AA) (P = 0.016) and a higher G allele frequency existed (P = 0.024) among all patients with knee OA and controls. On stratification analysis, the genotype GG and G allele were associated with susceptibility to knee OA in females, both young (≤65 years) and old groups (>65 years) and patients with mild knee OA.
  
  
  
  Our finding suggested that the genetic variant of LEPR gene rs1137101 is independently related to knee OA susceptibility in Northwest Chinese population with Han ethnicity and may serve as a potential biomarker to determine risk of knee OA.
authors.affiliation: Rehabilitation Center, First Affiliated Hospital of Xi'an Jiaotong University Health Science Center, No. 277, Yanta West Road, Xi'an, 710061, Shaanxi Province, People's Republic of China. yangjianhui1963@sina.com.
authors.forename: Jianhui
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Orthopedics, First Affiliated Hospital of Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi Province, People's Republic of China.
authors.forename: Heng
authors.initials: H
authors.lastname: Du
authors.affiliation: Rehabilitation Center, First Affiliated Hospital of Xi'an Jiaotong University Health Science Center, No. 277, Yanta West Road, Xi'an, 710061, Shaanxi Province, People's Republic of China.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Lv
authors.affiliation: Department of Statistics, Xi'an Jiaotong University Health Science Center, Xi'an, 710061, Shaanxi Province, People's Republic of China.
authors.forename: Lianhe
authors.initials: L
authors.lastname: Zhang
mesh_terms: D000368:Aged; D054458:Amplified Fragment Length Polymorphism Analysis; D001120:Arginine / Q000235:genetics; D044466:Asian People / Q000235:genetics*; D015415:Biomarkers; D016022:Case-Control Studies; D005006:Ethnicity / Q000235:genetics; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D005973:Glutamine / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D054411:Receptors, Leptin / Q000235:genetics*; D017422:Sequence Analysis, DNA; D012737:Sex Factors
chemical_list: D015415:Biomarkers; C515448:LEPR protein, human; D054411:Receptors, Leptin; D005973:Glutamine; D001120:Arginine
keywords: Gln223Arg; Knee OA; LEPR; SNPs