title: Two single-nucleotide polymorphisms in the DKK1 gene are associated with developmental dysplasia of the hip in the Chinese Han female population.
abstract: OBJECTIVE
  Developmental dysplasia of the hip (DDH) is a common congenital or acquired skeletal disease characterized by subluxation, dislocation, or dysplasia of the hip joint. This study aimed to explore the potential impact of Dickkopf-1 (DKK1) gene polymorphisms on embryonic hip joint development and the course of DDH.
  
  
  METHODS
  One hundred ninety-two unrelated Chinese Han female DDH patients and 191 unrelated, healthy, ethnically matched female controls were recruited and genotyped for two tag single-nucleotide polymorphisms (SNPs) of DKK1 using the Sequenom method.
  
  
  RESULTS
  One of the two DKK1 tag SNPs, rs11001560, was not shown to be significantly statistically different in allele frequency between DDH patients and control groups (χ(2)=0.898, df=1, p=0.343). However, a significant difference in genotype distribution was observed (χ(2)=21.987, df=2, p<0.0001). For SNP rs1569198, significant differences were observed in both allele frequency and genotype distribution between the DDH group and control group (χ(2)=31.484, df=1, p<0.0001 and χ(2)=30.323, df=2, p<0.0001). The A allele frequency of rs1569198 has a significant association to increased risk of DDH development (odds ratio [OR]=3.032, 95% confidence interval [95% CI]: 2.034-4.519).
  
  
  CONCLUSIONS
  In conclusion, the association between two tag SNPs of the DKK1 gene and DDH development reached statistical significance in our study population; the results of our genetic association analysis indicated that DKK1 may be a good candidate responsible for DDH development in the Chinese Han female population.
authors.affiliation: 1 Graduate School of Peking Union Medical College , Beijing, China .
authors.forename: Shengnan
authors.initials: S
authors.lastname: Liu
authors.forename: Wei
authors.initials: W
authors.lastname: Tian
authors.forename: Jing
authors.initials: J
authors.lastname: Wang
authors.forename: Longfei
authors.initials: L
authors.lastname: Cheng
authors.forename: Jian
authors.initials: J
authors.lastname: Jia
authors.forename: Xu
authors.initials: X
authors.lastname: Ma
mesh_terms: D000483:Alleles; D044466:Asian People / Q000208:ethnology / Q000235:genetics; D002681:China / Q000208:ethnology; D005260:Female; D005787:Gene Frequency; D060005:Genotyping Techniques; D006617:Hip Dislocation / Q000235:genetics*; D006801:Humans; D007223:Infant; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors
chemical_list: C501126:DKK1 protein, human; D036341:Intercellular Signaling Peptides and Proteins