title: PTPN22 -1123G > C polymorphism is associated with susceptibility to primary immune thrombocytopenia in Chinese population.
abstract: Primary immune thrombocytopenia (ITP) is an acquired autoimmune disorder characterized by autoantibody-mediated platelet destruction. Multiple factors have been implicated in ITP pathogenesis, including T-lymphocyte dysfunctions. The protein tyrosine phosphatase, non-receptor type 22 (PTPN22) gene encodes lymphoid-specific phosphatase (LYP), a critical negative regulator of T cell activation. Single nucleotide polymorphisms (SNPs) of PTPN22 have been broadly associated with susceptibilities to various autoimmune disorders. Here we conducted a case-control study investigating whether the PTPN22 -1123G > C SNP contributes to the risk of ITP in Chinese population. The study included 191 ITP cases and 216 ethnically matched normal controls. Genotyping of -1123G > C SNP was performed using a single-base extension (SBE) and mass spectrometry method. Allelic and genotypic frequencies were compared between the case-control groups by the chi-square test. We observed significant overrepresentation of -1123G allele (p = 0.034, odds ratio (OR) = 1.374, 95% confidence interval (CI) [1.024-1.843]) and GG genotype (P = 0.038, OR = 1.951, 95% CI [1.031-3.694]) in the patients compared with the controls. Stratified analysis by gender and age of disease onset revealed comparable observations in both male and adult ITP cohorts. These data suggest a moderate association of PTPN22 -1123G > C SNP with susceptibility to ITP. Together with previous reports, our finding provides further evidence for PTPN22 being a general autoimmunity gene.
authors.affiliation: State Key Laboratory of Experimental Hematology, Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin, PR China.
authors.forename: Jing
authors.initials: J
authors.lastname: Ge
authors.forename: Huiyuan
authors.initials: H
authors.lastname: Li
authors.forename: Dongsheng
authors.initials: D
authors.lastname: Gu
authors.forename: Weiting
authors.initials: W
authors.lastname: Du
authors.forename: Feng
authors.initials: F
authors.lastname: Xue
authors.forename: Tao
authors.initials: T
authors.lastname: Sui
authors.forename: Jianhui
authors.initials: J
authors.lastname: Xu
authors.forename: Renchi
authors.initials: R
authors.lastname: Yang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000483:Alleles; D044466:Asian People / Q000235:genetics*; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D002681:China; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D020641:Polymorphism, Single Nucleotide; D054596:Protein Tyrosine Phosphatase, Non-Receptor Type 22 / Q000235:genetics*; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000235:genetics*; D055815:Young Adult
chemical_list: D054596:Protein Tyrosine Phosphatase, Non-Receptor Type 22