Ahmadloo Somayeh, Taghizadeh Mohsen, Akhiani Mohsen, Salimzadeh Ahmad, Keramatipour Mohammad
Department of Medical Genetics, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran.
Department of Rheumatology, Alborz Hospital, Karaj, Iran.
Iran J Allergy Asthma Immunol. 2015 Aug;14(4):437-42.
The rs2476601 (R620W, C1858T) polymorphism in PTPN22 gene has been repeatedly reported to be associated with rheumatoid arthritis (RA). The rs 2476601 is widely suggested for predictive testing and risk assessment for RA. The aim of this study was to test the possible association of this SNP with RA in Iranian population. A total of 872 samples (405 confirmed RA patients and 467 healthy controls) were recruited in this study. Genomic DNA was extracted from whole blood and the genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR- RFLP). Genotyping for a set of samples were re-confirmed by two other rounds of genotyping, using another PCR-RFLP experiment with different enzyme and DNA sequencing. All 872 samples were genotyped as homozygous CC in first round of genotyping. Genotyping was repeated for 30% of samples by another restriction enzyme and for 10% of samples by sequencing. Again all samples showed homozygous CC genotype. This study suggests that the rs2476601 polymorphism of PTPN22 gene is mono-morphic in Iranian population, containing only C allele. Considering that previous studies in other populations reported the T allele as the risk allele at this locus, the present study concluded that rs2476601 play no role in susceptibility to RA and other autoimmune diseases in Iranian population. This finding has significant future clinical implications in determining the strategy for risk assessment and predictive testing for such diseases in Iranian population.
PTPN22基因中的rs2476601（R620W，C1858T）多态性已被多次报道与类风湿性关节炎（RA）相关。rs2476601被广泛推荐用于RA的预测性检测和风险评估。本研究的目的是检测该单核苷酸多态性（SNP）与伊朗人群RA的可能关联。本研究共招募了872个样本（405例确诊的RA患者和467例健康对照）。从全血中提取基因组DNA，并通过聚合酶链反应-限制性片段长度多态性（PCR-RFLP）进行基因分型。通过两轮其他基因分型对一组样本的基因分型进行重新确认，使用另一种不同酶的PCR-RFLP实验和DNA测序。在第一轮基因分型中，所有872个样本均被基因分型为纯合子CC。通过另一种限制酶对30%的样本重复进行基因分型，对10%的样本进行测序。所有样本再次显示为纯合子CC基因型。本研究表明，PTPN22基因的rs2476601多态性在伊朗人群中是单态的，仅包含C等位基因。鉴于之前在其他人群中的研究报道该位点的T等位基因为风险等位基因，本研究得出结论，rs2476601在伊朗人群对RA和其他自身免疫性疾病的易感性中不起作用。这一发现对于确定伊朗人群此类疾病的风险评估和预测性检测策略具有重要的临床意义。
