Molecular Biology Reports

, Volume 39, Issue 11, pp 9965–9970

Influence of BLK polymorphisms on the risk of rheumatoid arthritis

Article

Abstract

B cell lymphocyte kinase (BLK) encodes a member of the Src kinase family and thus may influence the proliferation and differentiation of cells. A single nucleotide polymorphism (SNP) located in the first intron of BLK has shown that the risk C allele of rs2248932 is associated with lower levels of messenger RNA expression of BLK. We hypothesized that this polymorphism may contribute to rheumatoid arthritis (RA) susceptibility. We studied BLK rs2248932 T/C gene polymorphisms in 329 patients with RA and 697 controls in a Chinese population. Genotyping was done using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). When the BLK rs2248932 TT homozygote genotype was used as the reference group, the CC genotype was associated with a significantly increased risk of RA. In the recessive model, when the BLK rs2248932 TT/TC genotypes were used as the reference group, the CC homozygote genotype was associated with a significantly increased susceptibility to RA. In stratification analyses, a significantly increased risk for RA associated with the BLK rs2248932 CC genotype was evident among younger patients, CRP-negative patients and anti-CCP-positive patients compared with the BLK rs2248932 TT/TC genotype. The risk was also significantly evident among RF-positive patients, patients with lower ESR levels, patients with lower or higher DAS28 score and patients with a lower functional class. These findings suggested that the functional SNP BLK rs2248932 T/C variant allele was associated with RA development. However, our results were obtained from a moderate-sized sample, and therefore this is a preliminary conclusion. Validation in a larger study from a more diverse ethnic population is needed to confirm these findings.

Keywords

BLK Polymorphisms Rheumatoid arthritis Molecular epidemiology 

Abbreviations

CI

Confidence interval

BLK

B cell lymphocyte kinase

LD

Linkage disequilibrium

OR

Odds ratio

SNP

Single nucleotide polymorphism

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Copyright information

© Springer Science+Business Media B.V. 2012

Authors and Affiliations

  1. 1.Department of OrthopedicsChangzhou Second People’s Hospital, Affiliated Hospital of Nanjing Medical UniversityChangzhouChina
  2. 2.School of Pharmaceutical Engineering & Life ScienceChangzhou UniversityChangzhouChina
  3. 3.Central LaboratoryChangzhou Second People’s Hospital, Affiliated Hospital of Nanjing Medical UniversityChangzhouChina

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