Association of PTPN22 C1858T polymorphism and type 1 diabetes: a meta-analysis

Recently, protein tyrosine phosphatase nonreceptor 22 (PTPN22) C1858T polymorphism has been identified as a susceptibile gene for type 1 diabetes (T1D), but studies are inconsistence, In order to assess the association between PTPN22C1858T polymorphism and T1D based on different ethnicities, a meta-analysis was performed, including 26 studies, total of 16,240 patients and 17,997 controls. Meta-analysis was performed on T versus C, T/T+T/C versus C/C (dominant model) and T/T versus T/C+C/C (recessive model) in a fixed/random effects model. The results indicated an association between the PTPN22 C1858T polymorphism and T1D in all subjects. The overall odds ratio (OR) of T versus C using the fixed effects model was 1.948 (95% CI = 1.859～2.041, P < 0.001). After stratification by ethnicity, analysis revealed that the PTPN22 C1858T polymorphism T allele was significantly associated with T1D in Europeans, Americans (OR = 1.946, 95% CI = 1.852~2.045, P < 0.001; OR = 1.946, 95% CI = 1.690~2.242, P < 0.001, respectively). Meta-analysis of the T/T+T/C genotype and the T/T genotypes showed the same results as that shown by the PTPN22 C1858T polymorphism T allele. This meta-analysis suggests a possible association between the PTPN22 C1858T polymorphism and T1D, especially in European and American populations.     

Association of PTPN22+1858C/T polymorphism with Type 1 diabetes in the North Indian population

A nonsynonymous SNP +1858C/T (rs2476601) in the protein tyrosine phosphatase, nonreceptor type 22(PTPN22) gene leading to Arg 620 Trp substitution is known to be associated with susceptibility to type 1 diabetes (T1D) and several other autoimmune diseases. We studied this polymorphism in 145 T1D patients and 210 healthy controls from North India. The minor allele +1858T was observed to be significantly increased among patients as compared to healthy controls (2.76% vs 0.5%, P = 0.027, OR = 5.93; 95% CI = 1.4–24.8). The association was also observed at the level of heterozygous C/T genotype (5.5% vs 0.95%, P = 0.026, OR = 6.07; 95% CI = 1.43–25.6). The T allele and C/T genotype were predominantly found among patients who were positive for both glutamic acid decarboxylase 65 (GAD65) and insulin antigen 2 (IA2) autoantibodies and showed significantly increased frequencies (10%, P = 0.034, OR = 11.67; 95% CI = 1.58–84.1 and 20%, P = 0.031, OR = 13.0; 95% CI = 1.66–97.5, respectively) as compared to patients negative for these autoantibodies (0.95% and 1.9%, respectively). The results suggest that the PTPN22+1858T allele is positively associated with T1D in the North Indian population.     

Susceptibility to type 1 diabetes conferred by the PTPN22 C1858T polymorphism in the Spanish population

Background

The protein tyrosine phosphatase N22 gene (PTPN22) encodes a lymphoid-specific phosphatase (LYP) which is an important downregulator of T cell activation. A PTPN22 polymorphism, C1858T, was found associated with type 1 diabetes (T1D) in different Caucasian populations. In this study, we aimed at confirming the role of this variant in T1D predisposition in the Spanish population.

Methods

A case-control was performed with 316 Spanish white T1D patients consecutively recruited and 554 healthy controls, all of them from the Madrid area. The PTPN22 C1858T SNP was genotyped in both patients and controls using a TaqMan Assay in a 7900 HT Fast Real-Time PCR System.

Results

We replicated for the first time in a Spanish population the association of the 1858T allele with an increased risk for developing T1D [carriers of allele T vs. CC: OR (95%) = 1.73 (1.17–2.54); p = 0.004]. Furthermore, this allele showed a significant association in female patients with diabetes onset before age 16 years [carriers of allele T vs. CC: OR (95%) = 2.95 (1.45–6.01), female patients vs female controls p = 0.0009]. No other association in specific subgroups stratified for gender, HLA susceptibility or age at onset were observed.

Conclusion

Our results provide evidence that the PTPN22 1858T allele is a T1D susceptibility factor also in the Spanish population and it might play a different role in susceptibility to T1D according to gender in early-onset T1D patients.     

Association between PTPN22 C1858T and type 1 diabetes: a replication in continental Italy

The missense PTPN22 C1858T polymorphism recently emerged as an important population-independent risk factor for type 1 diabetes (T1D) and other autoimmune diseases. The PTPN22 gene encodes the lymphoid tyrosine phosphatase (LYP), a negative regulator of signal transduction through the T-cell receptor. Although the frequency of the polymorphism is variable among different ethnic groups, the association between PTPN22 *T1858 and T1D has been replicated in several populations. Here, we contribute the first replication of the association between PTPN22 and T1D in populations from continental Italy, carried out in two independent samples of T1D patients ( N  = 216 and 82) and controls ( N  = 271 and 89). Our data also suggest that T1D carriers of the *T1858 allele could be at increased risk for other comorbid autoimmune disorders.     

Association study of PTPN22 C1858T polymorphism in Trypanosoma cruzi infection

In this study we investigated a possible role for the single nucleotide polymorphism C1858T of the PTPN22 (protein tyrosine phosphatase nonreceptor 22) gene in determining the susceptibility to Trypanosoma cruzi infection, as well as in development of chagasic heart disease. This study included 316 patients with Chagas' disease and 520 healthy individuals from Colombia and Peru. Genotyping of PTPN22 was performed by the real-time polymerase chain reaction technology, using the TaqMan 5' allelic discrimination assay. No statistically significant differences in the frequency of PTPN22 C1858T gene polymorphism between chagasic patients and controls or between asymptomatic and cardiomyopathic individuals were observed. Our findings suggest that the PTPN22 polymorphism analyzed does not play a major role in the development of Chagas' disease in the Colombian and Peruvian populations.     

Gender-specific association of the PTPN22 C1858T polymorphism with achalasia

The protein tyrosine phosphatase N22 (PTPN22) gene encodes a lymphoid-specific phosphatase (LYP), a downregulator of T-cell activation. Because a functional PTPN22 polymorphism, C1858T, has been found to be associated with different autoimmune diseases, we aimed to elucidate the role of this variant in predisposition to achalasia. We performed a case-control study with 231 nonrelated Spanish patients of white ethnicity diagnosed with achalasia and in 554 healthy control subjects, all genotyped for PTPN22 C1858T using TaqMan chemistry. The frequency of the 1858T allele was higher in the achalasia patients than in the healthy controls (carriers of allele T vs CC: OR = 1.38, 95% confidence interval [95% CI] 0.88-2.16, p = 0.13). Moreover a different genotype distribution was found between female and male patients (carriers of allele T vs CC: OR = 2.06, 95% CI 0.96-4.42, p = 0.04) and also between female patients and controls (OR = 1.94, 95% CI 1.12-3.36, p = 0.01), but not between male patients and controls (OR = 0.94, 95% CI 0.50-1.77, p = 0.85). We conclude that the PTPN22 1858T allele is a susceptibility factor for Spanish women with achalasia.     

PTPN22 C1858T polymorphism in Colombian patients with autoimmune diseases

A functional single nucleotide polymorphism (SNP) C1858T in the protein tyrosine phosphatase nonreceptor 22 (PTPN22) gene encoding an intracellular phosphatase with negative regulatory effects on T-cell activation is associated with some autoimmune diseases in Caucasians. Taking into account firstly, that SNP frequencies may vary across populations and, secondly, that replication studies are important to confirm previous associations, we examined the influence of PTPN22 polymorphism in 621 Colombian patients with four autoimmune diseases. Accordingly, 298 patients with rheumatoid arthritis (RA), 143 with systemic lupus erythematosus (SLE), 70 with primary Sjogren's syndrome (pSS) and 110 with Type 1 diabetes (T1D) were studied. The control group consisted of 308 matched healthy individuals. Genotyping of PTPN22 was performed by the real-time polymerase chain reaction technology, using the Taq Man 5'-allele discrimination assay. The 1858 T allele was found to be a risk factor for pSS (odds ratio (OR)=2.42), SLE (OR=2.56), and T1D (OR=1.83). A lower but nonsignificant trend was observed for RA (OR=1.26). These results confirm the influence of PTPN22 in autoimmunity and indicate that autoimmune phenotypes could represent pleiotropic outcomes of nonspecific disease genes that underlie similar immunogenetic mechanisms.     

Sex-specific association of the human PTPN22 1858T-allele with type 1 diabetes

Type 1 diabetes (T1D) is a common organ-specific autoimmune disease of complex aetiology, involving the interaction of a large number of disease-associated genes. By comparison of a Danish population sample of 253 Caucasian children and adolescents with T1D and a control group consisted of 354 unrelated healthy blood donors, the present study provides evidence of an isolated association of the disease-associated PTPN22 1858T-allele with T1D to the female sex. Furthermore, the present data suggest that PTPN22 genotypes affect the age of onset in a sex-specific manner. The increased frequency of the risk allele and its association with age at onset in female T1D children and adolescents indicates that the genetic contribution to disease pathogenesis is more prominent in females in this population of Danish patients.     

A functional polymorphism (1858C/T) in the PTPN22 gene is linked and associated with type I diabetes in multiplex families

Type I diabetes (T1D) is a complex disorder, which arises from the autoimmune destruction of the insulin-secreting beta cells of the pancreas leading to a life-long dependence on exogenous insulin. A recent study of T1D cases and controls provided evidence for association between an allele of a functional single-nucleotide polymorphism (SNP) in the PTPN22 gene and T1D. In the current study, this SNP was genotyped in a collection of 406 multiplex T1D families. Significant evidence of the combined presence of association and linkage to T1D was obtained (P = 2.5 x 10(-5)). Linkage studies in subsets of families defined by PTPN22 SNP genotypes suggest possible interaction with loci on chromosomes 3 and 21. Previous genome scans in this collection of T1D families, and others, have not yielded significant evidence of linkage in the region of the PTPN22 locus. However, the highly significant evidence of allelic association suggests that variation at, or near, this functional SNP contributes to the risk of T1D.     

Association of PTPN22 C1858T Polymorphism and Type 1 Diabetes: A Meta-analysis

Recently, protein tyrosine phosphatase nonreceptor 22 (PTPN22) C1858T polymorphism has been identi?ed as a susceptibile gene for type 1 diabetes (T1D), but studies are inconsistence, In order to assess the association between PTPN22C1858T polymorphism and T1D based on different ethnicities, a meta-analysis was performed, including 26 studies, total of 16,240 patients and 17,997 controls. Meta-analysis was performed on T versus C, T/T+T/C versus C/C (dominant model) and T/T versus T/C+C/C (recessive model) in a ?xed/random effects model. The results indicated an association between the PTPN22 C1858T polymorphism and T1D in all subjects. The overall odds ratio (OR) of T versus C using the fixed effects model was 1.948 (95% CI = 1.859～2.041, P < 0.001). After strati?cation by ethnicity, analysis revealed that the PTPN22 C1858T polymorphism T allele was signi?cantly associated with T1D in Europeans, Americans (OR = 1.946, 95% CI = 1.852～2.045, P < 0.001; OR = 1.946, 95% CI = 1.690～2.242, P < 0.001, respectively). Meta-analysis of the T/T+T/C genotype and the T/T genotypes showed the same results as that shown by the PTPN22 C1858T polymorphism T allele. This meta-analysis suggests a possible association between the PTPN22 C1858T polymorphism and T1D, especially in European and American populations.     

The putative role of the C1858T polymorphism of protein tyrosine phosphatase PTPN22 gene in autoimmunity

Autoimmune diseases represent a heterogeneous group of conditions whose incidence is increasing worldwide. This has stimulated studies on their etiopathogenesis, derived from a complex interaction between genetic and environmental factors, in order to improve prevention and treatment of these diseases.An increasing amount of epidemiologic investigations has associated the presence of the C1858T polymorphism in the protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene to the onset of several autoimmune diseases including insulin-dependent diabetes mellitus (Type 1 diabetes).PTPN22 encodes for the lymphoid tyrosine phosphatase Lyp. This belongs to non-receptor-type protein tyrosine phosphatases involved in lymphocyte activation and differentiation. In humans, Lyp may have a role in the negative regulation of T cell receptor signaling. The single nucleotide polymorphism C1858T encodes for a more active phosphatase Lyp R620W. This has the ability to induce a higher negative regulation of T cell receptor signaling. Thus, C1858T could play an important role at the level of thymocyte polarization and escape of autoreactive T lymphocytes, through the positive selection of otherwise negatively selected autoimmune T cells.In this review we discuss the physiological role exerted by the PTPN22 gene and its encoded Lyp product in lymphocyte processes. We highlight the pathogenic significance of the C1858T PTPN22 polymorphism in human autoimmunity with special reference to Type 1 diabetes.Recently the genetic variation in PTPN22 was shown to induce altered function of T and B-lymphocytes. In particular BCR signaling defects and alterations in the B cell compartment were reported in T1D patients. We finally speculate on the possible development of novel therapeutic treatments in human autoimmunity aiming to selectively target the variant Lyp protein in autoreactive T and B lymphocytes.     

Association of PTPN22 single nucleotide polymorphism with rheumatoid arthritis but not with allergic asthma

PTPN22 gene encodes a lymphoid tyrosine phosphatase (LYP), an important negative regulator of T-cell responses. The 1858C>T (Arg620Trp) single nucleotide polymorphism (rs2476601) was found associated with autoimmune diseases, including rheumatoid arthritis (RA). Allergic diseases are similar to autoimmune diseases, by an exaggerated immune response to an antigen (allergen in this case) normally not invoking such response in healthy individuals. We investigated whether polymorphism 1858C>T in PTPN22 gene is associated with susceptibility to allergic asthma and RA in a Polish population. PTPN22 was genotyped in 173 patients with RA, in 198 patients with allergic asthma, and in 543 controls using PCR-RFLP. The patients with RA differed from healthy controls in frequencies of PTPN22 1858C>T alleles (P=0.0004; odds ratio (OR), 1.8; 95% CI, 1.33-2.55) and genotypes (P=0.0009). Strong associations of 1858T allele with RA limited to joints (0.21 vs 0.12, P=0.0002; OR, 2.1; 95% CI, 1.44-3.00), with erosive disease (0.20 vs 0.12, P=0.0003; OR, 1.92; 95% CI, 1.34-2.71), with a lack of rheumatoid factor (RF; 0.23 vs 0.12, P=0.0008; OR, 2.29; 95% CI, 1.44-3.63), and weak association with the presence of RF (0.17 vs 0.12, P=0.02; OR, 1.6; 95% CI, 1.10-2.40) in comparison with healthy controls were observed. Very strong association of 1858T allele (P<0.0001; OR, 2.72; 95% CI, 1.9-3.9) and T phenotype (P<0001; OR, 3.2; 95% CI, 2.1-4.9) with antibodies to cyclic citrullinated peptide (CCP) was found. When patients with allergic asthma were typed for PTPN22 1858C>T polymorphism, no difference with control was found. Subdivision of patients into those with mild, moderate, or severe asthma did not reveal any associations. In conclusion, we confirmed associations between several clinical manifestations of RA and PTPN22 1858T allele. However, no association with 1858C>T polymorphism was found for susceptibility to allergic asthma or for severity of the disease.     

The 1858T PTPN22 gene variant contributes to a genetic risk of type 1 diabetes in a Ukrainian population

The 1858T variant of the protein tyrosine phosphatase gene, PTPN22, is associated with an increased risk of several autoimmune diseases. The aim of this study has been to investigate the possible association of 1858C-->T PTPN22 polymorphism and type 1 diabetes (T1D) in Caucasians from Ukraine. Overall, the distribution of 1858 PTPN22 genotypes differed significantly between the T1D patient group (n = 296) and the control group (n = 242) (P = 0.0036). When both groups were classified according to sex, the TT genotype and T allele showed a statistically significant higher frequency in T1D female patients (5.9 and 22.8%, respectively) in comparison with the female controls (0 and 11.9%) (P = 0.008 for both analyses). The patients with the TT genotype were significantly younger at the onset of T1D compared with those with genotypes TC and CC (P = 0.035 and 0.019, respectively). In our Ukrainian Caucasian cohort, we confirmed the association between T1D and the PTPN22,1858T allele.     

Association analysis of the 1858C>T polymorphism in the PTPN22 gene in juvenile idiopathic arthritis and other autoimmune diseases

A functional single nucleotide polymorphism, 1858C>T, in the PTPN22 gene, encoding a tyrosine phosphatase, has been reported to be associated with type I diabetes and some other autoimmune diseases. To further investigate whether this polymorphism may be a general susceptibility factor for autoimmunity, we performed an association study in five different autoimmune diseases, three previously not tested. We found an association with juvenile idiopathic arthritis (OR=1.41; P=0.04), not previously reported, and a tendency for an association with coeliac disease (OR=1.35; P=0.08). In primary sclerosing cholangitis, no association was observed (OR=0.95; P=0.8). Furthermore, we confirmed the increased risk in rheumatoid arthritis (OR=1.58; P=0.001), but could not find support for an association with systemic lupus erythematosus (OR=0.94; P=0.8). Altogether, we have provided further evidence of an association between autoimmune diseases and the 1858C>T polymorphism in PTPN22.     

ORIGINAL ARTICLE: PTPN22 C1858T Polymorphism in Women with Endometriosis

Citation Gomes FMCS, Bianco B, Teles JS, Christofolini DM, de Souza AMB, Guedes AD, Barbosa CP. PTPN22 C1858T polymorphismin women with endometriosis. Am J Reprod Immunol 2010; 63: 227–232 Problem Endometriosis has been suggested to be an autoimmune disease and recently, an allelic variation of the PTPN22 (C1858T) gene was revealed to be associated with the development of autoimmunity. The aim of the study was to determine the frequency of the PTPN22 (C1858T) polymorphism in Brazilian women with endometriosis as compared with controls. Method of study Case–control study included 140 women with endometriosis and a control group consisting of 180 healthy fertile women without a history of endometriosis and/or autoimmune diseases from the ABC School of Medicine. The PTPN22 (C1858T) polymorphism was studied by restriction fragment length polymorphism polymerase chain reaction (RFLP‐PCR). Results Genotypes CC, CT and TT of PTPN22 polymorphism presented frequencies of 67.9, 30.0 and 2.1% in the women with endometriosis (P = 0.008); 76.2, 19.0 and 4.8% in women with minimal/mild endometriosis (P = 0.173); 61.0, 39.0 and 0.0% in women with moderate/severe endometriosis (P ≤ 0.001) and 82.8, 16.1 and 1.1% in control group. Allele C and T were present in 82.9 and 17.1%; 85.7 and 14.3%; 80.5 and 19.5%; and 90.8 and 9.2% respectively, in women with endometriosis (P = 0.004), women with minimal/mild endometriosis (P = 0.148), women with moderate/severe endometriosis (P = 0.002) and control group. Conclusion The data suggest that in Brazilian women polymorphism PTPN22 (C1858T) may be an important genetic predisposing factor for endometriosis, especially, in advanced disease.     

Type 1 diabetes linked PTPN22 gene polymorphism is associated with the frequency of circulating regulatory T cells

Dysfunction of FOXP3-positive regulatory T cells (Tregs) likely plays a major role in the pathogenesis of multiple autoimmune diseases including type 1 diabetes (T1D). Whether genetic polymorphisms associated with the risk of autoimmune diseases affect Treg frequency or function is currently unclear. Here, we analysed the effect of T1D-associated major HLA class II haplotypes and seven single nucleotide polymorphisms in six non-HLA genes [INS (rs689), PTPN22 (rs2476601), IL2RA (rs12722495 and rs2104286), PTPN2 (rs45450798), CTLA4 (rs3087243), and ERBB3 (rs2292239)] on peripheral blood Treg frequencies. These were determined by flow cytometry in 65 subjects who had progressed to T1D, 86 islet autoantibody-positive at-risk subjects, and 215 islet autoantibody-negative healthy controls. The PTPN22 rs2476601 risk allele A was associated with an increase in total (p = 6 × 10⁻⁶) and naïve (p = 4 × 10⁻⁵) CD4+CD25+CD127lowFOXP3+ Treg frequencies. These findings were validated in a separate cohort comprising ten trios of healthy islet autoantibody-negative children carrying each of the three PTPN22 rs2476601 genotypes AA, AG, and GG (p = 0.005 for total and p = 0.03 for naïve Tregs, respectively). In conclusion, our analysis implicates the autoimmune PTPN22 rs2476601 risk allele A in controlling the frequency of Tregs in human peripheral blood.     

C1858T functional variant of PTPN22 gene is not associated with celiac disease genetic predisposition

Recent findings have demonstrated that the single nucleotide polymorphism 1858C-->T located at the P1 motif of the PTPN22 (protein tyrosine phosphatase nonreceptor 22) gene has functional relevance and is associated with a variety of autoimmune diseases. The aim of this study was to assess the role of the PTPN22 1858C-->T polymorphism in the genetic predisposition to celiac disease (CD). We analyzed a case-control cohort composed by 534 patients with CD and 653 healthy controls and additionally a panel of 271 celiac families. The PTPN22 1858C-->T genotyping was performed by TaqMan 5' allelic discrimination assay. We did not observed any statistically significant deviation after comparing allele and genotypic frequencies of PTPN22 1858C-->T between patients with CD and controls. Accordingly, the familial analysis did not reach statistically significant deviation in the transmission of PTPN22 1858C-->T alleles to the affected offspring. Therefore, our data suggest that the PTPN22 1858 single nucleotide polymorphism has no, or only a negligible, effect on CD susceptibility in this Spanish population.     

Interplay between PTPN22 C1858T polymorphism and cow's milk formula exposure in type 1 diabetes

Genetic heterogeneity may affect the analysis of risk factors associated with type 1 diabetes (T1D). We studied the effect of the INS −23A/T, PTPN22 1858C/T, and CTLA-4 +49A/G polymorphisms on the emergence of T1D-associated autoimmunity in children exposed to cow's milk (CM) based formula during early or late infancy. The study comprised of 156 children from the Finnish DIPP cohort who had developed ≥ 2 types of autoantibodies (ICA, IAA, GADA or IA-2A) or clinical T1D and 563 control children. The PTPN22 1858T allele was associated with the appearance of the autoantibodies and clinical T1D among children exposed to CM formula before the age of 6 months (PTPN22: for all P ≤ 0.001, Log Rank test), but not among children exposed later on. Cox regression analysis showed an interaction between early CM exposure and 1858T allele and enhanced appearance of ICA, IAA and IA-2A (for all P ≤ 0.04). Our results imply that the PTPN22 polymorphism affects the development of T1D-associated autoimmunity only if children are exposed to CM formula during early infancy suggesting an interplay between genetic and environmental factors. This may provide an explanation for the contradictory findings on the significance of CM formula exposure in T1D.     

肌钙蛋白T基因单核苷酸多态性与运动性横纹肌溶解症的关联研究

 目的：分析慢肌型肌钙蛋白T（sTnT）基因第7内含子C7761T位点与快肌型肌钙蛋白T（fTnT）基因第8内含子T7955C位点单核苷酸多态性与大强度训练后血清肌酸激酶（CK）活性之间的关系,探索运动性横纹肌溶解症（ERM）的可能遗传机制。方法：85名武警战士进行一次大强度负重训练造成亚临床ERM,检测血清CK活性的时程变化;PCR-RFLP法测定sTnT（C7761T）和fTnT（T7955C）基因多态性;分析基因多态性与安静CK（CK rest）、峰值CK（CK peak）以及CK最大变化值（ΔCK max）之间的关系。结果：sTnT和fTnT基因型分布频率均符合哈-温平衡定律。sTnT基因：C/T和C/C基因型组CK rest均高于T/T基因型组（均P<0.01）,CK peak和ΔCK max在各组间无显著差异（均P>0.05）,（T/T+C/T）组CK rest低于CC基因型组（P<0.05）。fTnT基因：T/C基因型组和C/C基因型组CK rest均低于T/T基因型组（分别为P<0.05和P<0.01）,C/C基因型组CK peak和ΔCK max均低于T/T基因型组和T/C基因型组（均P<0.01）,（T/T+T/C）组CK peak和ΔCK max均高于C/C基因型组（均P<0.01）。结论：fTnT基因第8内含子T7955C位点单核苷酸多态性可作为ERM易感性的分子遗传学标记,T等位基因携带者是患ERM的高危人群。