title: Vitamin D receptor polymorphisms in immune thrombocytopenic purpura.
abstract: BACKGROUND
  Vitamin D receptor (VDR) polymorphisms have been studied in immune-mediated disorders, but not yet in immune thrombocytopenic purpura (ITP). We investigated whether VDR variants were associated with ITP in children.
  
  
  METHODS
  The study included 44 children with a diagnosis of ITP and 100 healthy controls. Five VDR polymorphisms (Cdx-2, FokI, BsmI, ApaI and TaqI) were genotyped and used to evaluate the association of VDR variants with ITP.
  
  
  RESULTS
  The distribution of the three Cdx-2 genotype groups (GG, GA, and AA) was significantly different between ITP patients and controls (P = 0.025); the homozygous GG genotype of Cdx-2 was overrepresented in ITP patients. The frequency of the A allele of Cdx-2 was significantly different between patients and controls (P = 0.01). The A allele of Cdx-2 was associated with a decreased risk of ITP (OR, 0.343; 95% CI: 0.150-0.782). No statistically significant difference was found between the ITP group and control group for Fok1, Bsm1, Apa1, and Taq1 polymorphisms (P > 0.5).
  
  
  CONCLUSIONS
  There appears to be an interaction between the Cdx-2 variant of VDR and childhood immune thrombocytopenia.
authors.affiliation: Department of Pediatric Oncology and Hematology, Dr Sami Ulus Maternity and Children's Health and Diseases Training and Research Hospital, Ankara, Turkey.
authors.forename: Sule
authors.initials: S
authors.lastname: Yesil
authors.affiliation: Department of Pediatric Oncology and Hematology, Dr Sami Ulus Maternity and Children's Health and Diseases Training and Research Hospital, Ankara, Turkey.
authors.forename: Hikmet Gulsah
authors.initials: HG
authors.lastname: Tanyildiz
authors.affiliation: Department of Pediatric Oncology and Hematology, Dr Sami Ulus Maternity and Children's Health and Diseases Training and Research Hospital, Ankara, Turkey.
authors.forename: Sibel Akpinar
authors.initials: SA
authors.lastname: Tekgunduz
authors.affiliation: Department of Pediatric Oncology and Hematology, Dr Sami Ulus Maternity and Children's Health and Diseases Training and Research Hospital, Ankara, Turkey.
authors.forename: Sule
authors.initials: S
authors.lastname: Toprak
authors.affiliation: Department of Pediatric Oncology and Hematology, Dr Sami Ulus Maternity and Children's Health and Diseases Training and Research Hospital, Ankara, Turkey.
authors.forename: Ali
authors.initials: A
authors.lastname: Fettah
authors.affiliation: Department of Public Health, Medicine Faculty, Gazi University, Ankara, Turkey.
authors.forename: Asiye Ugras
authors.initials: AU
authors.lastname: Dikmen
authors.affiliation: Department of Pediatric Oncology and Hematology, Dr Sami Ulus Maternity and Children's Health and Diseases Training and Research Hospital, Ankara, Turkey.
authors.forename: Gurses
authors.initials: G
authors.lastname: Sahin
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D005260:Female; D005819:Genetic Markers; D005838:Genotype; D060005:Genotyping Techniques; D006801:Humans; D007223:Infant; D008297:Male; D020641:Polymorphism, Single Nucleotide; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000235:genetics*; D018167:Receptors, Calcitriol / Q000235:genetics*
chemical_list: D005819:Genetic Markers; D018167:Receptors, Calcitriol; C579457:VDR protein, human
keywords: Vitamin D receptor; children; immune thrombocytopenic purpura; polymorphism