title: Interleukin-18 gene promoter--607 A/C polymorphism and the risk of immune thrombocytopenia.
abstract: Interleukin-18 (IL-18) is a T helper 1 cytokine, which is postulated to play a role in immune thrombocytopenia (ITP). The aim of this study was to determine whether IL-18 promoter gene -607 A/C polymorphism was associated with ITP. Three-hundred and fifty-four Chinese ITP patients and 300 Chinese healthy individuals were enrolled. Genomic DNA was extracted from the peripheral blood. Polymerase chain reaction-restriction fragment length polymorphism (RFLP) was used to genotype the DNA samples for single nucleotide polymorphism (SNP)-607. Allelic and genotypic frequencies were compared between the case-control groups by the chi-square test. The results showed that the frequencies of the CC, CA and AA genotypes and C and A allele were 32.4, 47.8, 19.8, 56.4 and 43.6% in ITP patients and 32.3, 50.4, 17.3, 57.5 and 42.5% in the controls, respectively. There was no significant difference in either genotypes or allelic distribution between ITP patients and the controls. Furthermore, stratified analysis by the platelet count, age and disease course including ITP with severe thrombocytopenia (sITP), non-sITP, acute adult, chronic adult, acute childhood and chronic childhood revealed no significant difference in genotype and alleles distribution. In conclusion, this polymorphism was almost equally distributed between ITP patients and the controls. These data showed that this SNP may not be used as a stratification marker to predict the susceptibility to Chinese ITP.
authors.affiliation: Key Laboratory of Cancer Prevention and Therapy, Department of Hematology and Oncology, Tianjin Medical University Cancer Institute and Hospital, National Clinical Research Center for Cancer , Tianjin , PR China and.
authors.forename: Haifeng
authors.initials: H
authors.lastname: Zhao
authors.forename: Yizhuo
authors.initials: Y
authors.lastname: Zhang
authors.forename: Gangfeng
authors.initials: G
authors.lastname: Xiao
authors.forename: Ningning
authors.initials: N
authors.lastname: Wu
authors.forename: Jianfen
authors.initials: J
authors.lastname: Xu
authors.forename: Zhi
authors.initials: Z
authors.lastname: Fang
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D000368:Aged; D000483:Alleles; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D002681:China; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D006801:Humans; D020382:Interleukin-18 / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide; D011401:Promoter Regions, Genetic; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000235:genetics* / Q000276:immunology; D055815:Young Adult
chemical_list: D020382:Interleukin-18
keywords: IL-18; ITP; polymorphism