PTPN22 1858C>T polymorphism distribution in Europe and association with rheumatoid arthritis: case-control study and meta-analysis

Objective

The PTPN22 rs2476601 polymorphism is associated with rheumatoid arthritis (RA); nonetheless, the association is weaker or absent in some southern European populations. The aim of the study was to evaluate the association between the PTPN22 rs2476601 polymorphism and RA in Italian subjects and to compare our results with those of other European countries, carrying out a meta-analysis of European data.

Methods

A total of 396 RA cases and 477 controls, all of Italic ancestry, were genotyped for PTPN22 rs2476601 polymorphism. Patients were tested for autoantibodies positivity. The meta-analysis was performed on 23 selected studies.

Results

The PTPN22 T1858 allele was significantly more frequent in RA patients compared to controls (5.7% vs. 3.7%, p = 0.045). No clear relationship arose with the autoantibodies tested. The 1858T allele frequency in Italian RA patients was lower than the one described in northern European populations and similar to the frequency found in Spain, Turkey, Greece, Tunisia. A clear-cut North-South gradient arose from the analysis.

Conclusions

The PTPN22 T1858 allele is associated with RA in the Italian population. A North-South gradient of the allele frequency seems to exist in Europe, with a lower prevalence of the mutation in the Mediterranean area.     

The association between the PTPN22 C1858T polymorphism and systemic sclerosis: a meta-analysis

The aim of this study was to determine whether the functional protein tyrosine phosphatase nonreceptor 22 (PTPN22) C1858T polymorphism (rs2476601) confers susceptibility to systemic sclerosis (SSc) in different ethnic populations. A meta-analysis was conducted on the PTPN22 C1858T polymorphism across twelve comparative studies containing 4,367 SSc patients and 4,771 normal control subjects. The analysis showed an association between the PTPN22 1858T allele and SSc in all study subjects (OR [odds ratio] 1.169, 95% confidence interval [CI] 1.051, 1.300, P = 0.004). Analysis after stratification by ethnicity indicated that the PTPN22 1858T allele was significantly associated with SSc in Europeans (OR 1.147, 95% CI 1.029, 1.278, P = 0.013), and analysis showed an association between the T allele and SSc in anti-centromere antibody (ACA)-positive European subjects (OR 1.220, 95% CI 1.051, 1.417, P = 0.009). However, no association was found between the allele and anti-topoisomerase antibody (ATA)-positive SSc European patients (OR 1.1786, 95% CI 0.979, 1.417, P = 0.083). In addition, African Americans were found to have a much lower prevalence of the T allele (1.5%) than any other population studied, and Europeans had the highest prevalence (8.2%). This meta-analysis confirms that the PTPN22 C1858T polymorphism is associated with SSc susceptibility and ACA status in Europeans, and that its prevalence is dependent on ethnicity.     

The association between the PTPN22 C1858T polymorphism and rheumatoid arthritis: a meta-analysis update

The aim of this study was to determine whether the protein tyrosine phosphatase nonreceptor 22 (PTPN22) C1858T polymorphism confers susceptibility to rheumatoid arthritis (RA) in populations with different ethnicities. A meta-analysis was conducted on the PTPN22 C1858T polymorphism involving eighteen studies, which in total contained 20344 RA patients and 21828 controls. Meta-analysis revealed an association between the PTPN22 C1858T polymorphism T allele and RA in all subjects (odds ratio [OR] = 1.637, 95% confidence interval [CI] = 1.514–1.770, P < 0.001). After stratification by ethnicity, analysis indicated that the PTPN22 C1858T polymorphism T allele was significantly associated with RA in Europeans and Non-Europeans (OR = 1.587, 95% CI = 1.486–1.696, P < 0.001; OR = 1.748, 95% CI = 1.274–2.398, P < 0.001). Meta-analysis of the CT + TT genotype showed the same result patterns as that shown by the PTPN22 C1858T polymorphism T allele. Furthermore, a direct comparison between rheumatoid factor (RF)-positive and -negative subjects revealed a significant association with the T allele in RA patients with RF, but not in subjects without RF. In conclusion, this meta-analysis confirms that the PTPN22 C1858T polymorphism is associated with RA susceptibility in different ethnic groups, especially in Europeans, and the PTPN22 C1858T polymorphism T allele is significantly more prevalent in RF-positive patents than in RF-negative patients.     

Protein tyrosine phosphatase non-receptor type 22 (PTPN22) +1858 C>T gene polymorphism in Egyptian cases with rheumatoid arthritis

Background

Rheumatoid arthritis (RA) is a common autoimmune disease with a complex genetic background. The gene encoding protein tyrosine phosphatase non-receptor type 22 (PTPN22) has been reported to be associated with RA in several populations.

Objectives

This work aimed at assessing the association of PTPN22 +1858 C>T gene polymorphism with the susceptibility, activity and severity of RA in Egyptian subjects.

Subjects and methods

This study included 112 unrelated RA patients who were compared to 122 healthy unrelated individuals taken from the same locality. For all subjects, DNA was genotyped for PTPN22 +1858 C>T (rs2476601) polymorphism using the PCR-RFLP technique. Antibodies to cyclic citrullinated peptides (anti-CCP) were measured by enzyme-linked immunosorbent assay (ELISA).

Results

Cases showed significantly higher PTPN22 +1858 T allele carriage rate (CT + TT genotypes) compared to controls (34.8% vs. 8.2%, OR = 5.98, 95% CI = 2.81–12.73, p < 0.001). Also the frequency of the PTPN22 +1858 T allele was significantly higher among cases compared to controls (18.7% vs. 4.5%, OR = 4.89; 95% CI = 2.45–9.76, p < 0.001). Cases positive to the PTPN22 T allele (CT + TT genotypes) showed no significant difference from those with the CC genotype regarding clinical and immune parameters. Nonetheless, they showed a more functional disability presented in their significantly higher health assessment questionnaire (HAQ) score (p = 0.04).

Conclusions

This study is a confirmatory evidence of the association of the PTPN22 +1858 T allele with susceptibility and functional disability of RA in Egyptian subjects.     

The PTPN22-1858C>T (R620W) functional polymorphism is associated with generalized vitiligo in the Romanian population

Generalized vitiligo is an autoimmune disorder of the skin in which autoimmune-mediated destruction of melanocytes leads to depigmented patches of skin and overlying hair. The 1858C>T (R620W) functional polymorphism of the PTPN22 gene, which encodes lymphoid protein tyrosine phosphatase (Lyp), has been associated with susceptibility to a number of autoimmune disorders, including generalized vitiligo. The aim of this study was to test genetic association of the PTPN22 1858C>T variant and generalized vitiligo in a Romanian case-control cohort. We observed significant association of generalized vitiligo with the 1858T risk allele of PTPN22 [P = 0.0138; OR = 2.92 (1.21-7.03)], with significantly different distribution of PTPN22 1858C>T genotypes in cases versus controls [P = 0.036; OR = 2.69 (1.07-6.80)]. Our results provide evidence that the PTPN22 1858T allele contributes to risk of generalized vitiligo in European Caucasian populations, and underscores the importance of a genetically mediated autoimmune mechanism in the pathogenesis of vitiligo.     

<Emphasis Type="Italic">PTPN22</Emphasis> 1858C>T (R620W) functional polymorphism and human longevity

The PTPN22 gene, located on chromosome 1p13, encoding lymphoid protein tyrosine phosphatase (LYP), plays a crucial role in the negative control of T lymphocyte activation. Since the age-related change in T-cell signal transduction may be one of the most important causes of cell-mediated immune response decline with ageing, we performed a population-based association study to test whether the PTPN22 1858C>T (R620W) functional polymorphism affects the ability to survive to old age and to reach even exceptional life expectancy. 892 unrelated healthy individuals (age range 8–106 years, 403 males and 489 females) from central Italy were studied. For both gender, the frequency of PTPN22*T1858 carriers does not differ significantly in nona/centenarians and in octogenarians respect to young group. Allele and genotype frequencies of age groups were compared to those reported in previously published studied carried out on control individuals with Italic ancestry (N = 1393), further confirming results obtained from our sample population. Overall, our study suggests that PTPN22*T1858 allele is not negatively selected at oldest ages and we speculate that its increased ability to protect individuals against development of infectious diseases may counteract its deleterious effect on immune system leading to autoimmunity.     

Genetic association of the R620W polymorphism of protein tyrosine phosphatase PTPN22 with human SLE

We genotyped 525 independent North American white individuals with systemic lupus erythematosus (SLE) for the PTPN22 R620W polymorphism and compared the results with data generated from 1,961 white control individuals. The R620W SNP was associated with SLE (genotypic P=.00009), with estimated minor (T) allele frequencies of 12.67% in SLE cases and 8.64% in controls. A single copy of the T allele (W620) increases risk of SLE (odds ratio [OR]=1.37; 95% confidence interval [CI] 1.07-1.75), and two copies of the allele more than double this risk (OR=4.37; 95% CI 1.98-9.65). Together with recent evidence showing association of this SNP with type 1 diabetes and rheumatoid arthritis, these data provide compelling evidence that PTPN22 plays a fundamental role in regulating the immune system and the development of autoimmunity.     

PTPN22 C1858T and the risk of psoriasis: a meta-analysis

Psoriasis is a chronic autoimmune skin disease with both environmental and genetic risk factors. Previous studies of the association between psoriasis and PTPN22 C1858T (rs2476601), a gain of function variant associated with a stronger inhibitory effect of T-lymphocytes, have produced inconsistent results. The purpose of the current study is to evaluate the association between PTPN22 C1858T and psoriasis using meta-analysis to: (1) have a sufficient sample size for detecting a weak association; and (2) to explore the heterogeneity between studies. A meta-analysis based on random-effects model was performed with ten studies (3,334 psoriasis cases and 5,753 controls) identified from a literature search. A non-significantly positive association between psoriasis and the PTPN22 T1858 was observed [summary allelic odds ratio (OR) = 1.15, 95 % confidence interval (CI): 1.00-1.33] and the association appears stronger among subjects with psoriatic arthritis (summary allelic OR = 1.23, 95 % CI: 1.00-1.52). A null association between PTPN22 T1858 and early-onset psoriasis was observed (summary allelic OR = 1.08, 95 % CI: 0.92-1.28). The current analysis showed a non-significantly positive association between psoriasis and the PTPN22 T1858 allele, and the association appeared stronger among subjects with psoriatic arthritis. Future studies of psoriasis should incorporate gene-environment interaction in the analysis and pay attention to the heterogeneity of psoriasis cases and bias associated with population stratification.     

No association of PTPN22 R620 W gene polymorphism with rheumatic heart disease and systemic lupus erythematosus

Rheumatic heart disease (RHD) or acute rheumatic fever (ARF) develops as a consequence of an exaggerated immune response to Group A beta haemolytic streptococci causing pharyngitis. The molecular mimicry appears between human cardiac myosin and M protein of group A streptococcal membranes. The polymorphism of the protein tyrosine phosphatase nonreceptor 22 (PTPN22) gene, which encodes an important negative regulator of T cell activation, has been reported to be associated with susceptibility to several autoimmune diseases such as SLE and RA. The objective of this study was to investigate whether PTPN22 R620W polymorphism confers susceptibility to RHD in Turkish population. PTPN 22 R620W (rs2476601, A/G) polymorphism was genotyped by PCR-RFLP in 121 patients with RHD who fulfilling the revised classification criteria of Jones, and 160 healthy control (HC), and also 137 SLE as a diseased–control. The frequency of GG and AG genotypes were found to be 94% (114), 6% (7) in RHD, respectively and 96% (153) and 4% (7) in HC, respectively. The homozygous AA genotype was not present in RHD and HC. There was no statistically significant difference between RHD and HC according to the frequency of AG heterozygote genotype (P = 0.831; OR = 1.13; 95% CI 0.37–3.46). The frequency of the rare allele A was also very similar in RHD patients and HC (3, 2% respectively). A similar result was also found between SLE and HC. Our results demonstrated that the PTPN22 R620W polymorphism is not associated with RHD nor with SLE in Turkish population.     

Association between the <Emphasis Type="Italic">PTPN22</Emphasis>+1858 C/T polymorphism and psoriatic arthritis

Introduction  

The purpose of the present study was to investigate the frequency of the PTPN22 +1858 C/T single nucleotide polymorphism (SNP) (rs 2476601), previously shown to be associated with several autoimmune diseases, in patients with psoriatic arthritis (PsA) in comparison with population based controls.     

The protein tyrosine phosphatase nonreceptor 22 C1858T polymorphism and vasculitis: a meta-analysis

The aim of this study was to determine whether the functional protein tyrosine phosphatase nonreceptor 22 (PTPN22) C1858T polymorphism (rs2476601) confers susceptibility to vasculitis. A meta-analysis was conducted on the PTPN22 C1858T polymorphism across nine comparative studies containing 1,922 vasculitis patients and 11,505 normal control subjects. Meta-analysis showed no association between the T allele and vasculitis in all subjects [odds ratio (OR) 1.046, 95 % confidence interval (CI) 0.755-1.1.451, p = 0.786], and analysis after stratification by ethnicity indicated that the T allele was not associated with vasculitis in Europeans (OR 1.104, 95 % CI 0.798-1.528, p = 0.551). However, meta-analysis showed a significant association between the T allele and anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) (OR 1.415, 95 % CI 1.228-1.630, p = 1.59 × 10(-6)) and Wegener's granulomatosis (WG) (OR 1.829, 95 % CI 1.377-2.431, p = 3.09 × 10(-5)). In addition, meta-analysis showed an association between the T allele and WG in ANCA-positive subjects (OR 2.042, 95 % CI 1.534-2.719, p = 1.02 × 10(-6)), but not in ANCA-negative WG patients (OR 0.595, 95 % CI 0.199-1.781, p = 0.353). This meta-analysis does not show that the PTPN22 C1858T polymorphism is associated with vasculitis susceptibility, but does show that this polymorphism is associated with susceptibility to AAV, WG, and ANCA status in WG.     

Association of PTPN22 1858 single-nucleotide polymorphism with rheumatoid arthritis in a German cohort: higher frequency of the risk allele in male compared to female patients

The functional single-nucleotide polymorphism (SNP) of the gene PTPN22 is a susceptibility locus for rheumatoid arthritis (RA). The study presented here describes the association of the PTPN22 1858T allele with RA in a German patient cohort; 390 patients with RA and 349 controls were enrolled in the study. For 123 patients, clinical and radiographic documentation over 6 years was available from the onset of disease. Genotyping of the PTPN22 1858 SNP was performed using an restriction fragment length polymorphism PCR-based genotyping assay. The odds ratio to develop RA was 2.57 for carriers of the PTPN22 1858T allele (95% confidence interval (CI) 1.85–3.58, p < 0.001), and 5.58 for homozygotes (95% CI 1.85–16.79). The PTPN22 1858T allele was significantly associated not only with rheumatoid factor (RF) and anti-cyclic citrullinated peptide (CCP) positive RA, but also with RF and anti-CCP negative disease. The frequency of the PTPN22 1858T allele was increased disproportionately in male patients (53.8% compared to 33.0% in female patients, p < 0.001), and the resulting odds ratio for male carriers was increased to 4.47 (95% CI 2.5–8.0, p < 0.001). Moreover, within the male patient population, the rare allele was significantly associated with the HLA-DRB1 shared epitope (p = 0.01). No significant differences in disease activity or Larsen scores were detected. The results provide further evidence that the PTPN22 1858T allele is associated with RA irrespective of autoantibody production. The increased frequency of the risk allele in male patients and its association with the shared epitope indicate that the genetic contribution to disease pathogenesis might be more prominent in men.     

PTPN22 gene polymorphism in Egyptian alopecia areata patients and its impact on response to diphencyprone immunotherapy

PTPN22 1858C>T gene polymorphism has been associated with several autoimmune disorders including alopecia areata. The aim of the current study was to investigate the effect of the inherited genetic polymorphism 1858C>T of PTPN22 gene on the predisposition to severe forms of alopecia areata and its effect on the response to DPC treatment. To achieve our aim, PTPN22 1858C>T genotyping was performed by PCR-based restricted fragment length polymorphism (PCR-RFLP) analysis. The study included 103 Egyptian patients with extensive alopecia areata treated by DPC. Hundred healthy age and sex matched blood donors were included in the current study as a control group. Results of genotyping showed that PTPN22 CT and TT mutant genotypes were significantly higher in AA patients compared to controls and conferred increase risk of AA (OR = 2.601, 95% CI = 1.081–6.255). Statistical comparison between AA patients with wild and mutant genotypes revealed that the duration of the illness was significantly longer in those harboring the mutant genotypes. Moreover, the association of other autoimmune diseases as atopy and diabetes mellitus was higher in patients with mutant genotypes. Furthermore, PTPN22 1858C>T genetic polymorphism did not affect the patients' response to DPC immunotherapy.     

Association between 242C>T polymorphism of NADPH oxidase p22phox gene (CYBA) and longevity in Russian population

Life span depends on many factors, including the level of reactive oxygen species, like superoxide radical. Superoxide radical is produced from oxygen in the course of the oxidation of NADPH to NADP⁺. The process is catalyzed by NADPH oxidase. In this study, genotype and allele distributions of the C242T (rs4673) polymorphism in the CYBA gene, which encodes the α subunit of NADPH oxidase (p22phox), were examined in the sample of long livers and in the population sample of the city of Tomsk. Statistically significantly higher frequency of T allele among female long livers (34.625%), compared to the females from Russian population (26.32%) was demonstrated (χ² = 5.226; p = 0.022; OR = 1.48). Thus, the T allele is associated with a high life expectancy in females from the Russian population. No such association was observed for males from the same population.     

PTPN22 gene functional polymorphism (rs2476601) in older adults with frailty syndrome

The frailty syndrome is a common clinical marker of vulnerability in older adults conducive to an overall decline in inflammatory stress responsiveness; yet little is known about the genetic risk factors for frailty in elderly. Our aim was to investigate the association between the rs2476601 polymorphism in PTPN22 gene and susceptibility to frailty in Mexican older adults. Data included 630 subjects 70 and older from The Coyoacán cohort, classified as frail, pre-frail, and non-frail following Fried’s criteria. Sociodemographic and clinical characteristics were compared between groups at baseline and after a multivariate analysis. The rs2476601 polymorphism was genotyped by TaqMan genotyping assay using real-time PCR and genotype frequencies were determined for each frailty phenotype in all participants and subsets by age range. Genetic association was examined using stratified and interaction analyses adjusting for age, sex and variables selected in the multivariate analysis. Disability for day-life activities, depression and cognitive impairment were associated with the risk of pre-frailty and frailty at baseline and after adjustment. Carrying the T allele increased significantly the risk of frailty in patients 76 and older (OR 5.64, 95% CI 4.112–7.165) and decreased the risk of pre-frailty under no clinical signs of depression (OR 0.53; 95% CI 0.17–1.71). The PTPN22 polymorphism, rs2476601, could be a genetic risk factor for frailty as subject to quality of life. This is the first study analyzing such relationship in Mexican older adults. Confirming these findings requires additional association studies on wider age ranges in populations of older adults with frailty syndrome.

     

Protein tyrosine phosphatase non-receptor type 22 gene polymorphism C1858T is not associated with leprosy in Azerbaijan,Northwest Iran

BACKGROUND:

Leprosy (Hansen''s disease) is a human chronic granulomatous infectious disease caused by Mycobacterium leprae. Several types of study support a role for host genetics in susceptibility to leprosy. The protein tyrosine phosphatase non-receptor type 22 (PTPN22) gene encodes an intracellular lymphoid protein tyrosine phosphatase that has been shown to play a negative regulatory role in T-cell activation.

AIMS:

The aim of the present study was to find out associating the PTPN22 C1858T (R620W) polymorphism and leprosy in the Azeri population from Northwest Iran.

MATERIALS AND METHODS:

A total of 153 treated leprosy patients and 197 healthy and ethnic matched controls entered this study. We used restriction fragment length polymorphism method to type PTPN22 C1858T polymorphism.

RESULTS:

There was no significant difference in distribution of genotype and allele frequencies of PTPN22 C1858T polymorphism between leprosy patients and controls (P = 0.641 and 0.645; respectively). Moreover, there was no significant association between different clinical findings (karnofsky performance status score, clinical forms and manifestations of leprosy) and PTPN22 C1858T polymorphism. Data showed a low frequency of the minor (T) allele by 2.3% in leprosy and 1.5% in healthy individuals.

CONCLUSIONS:

The PTPN22 C1858T (R620W) is not relevant in susceptibility to leprosy in the Azeri population of Northwest Iran.     

The <Emphasis Type="Italic">PTPN22</Emphasis>1858C/T polymorphism is associated with anti-cyclic citrullinated peptide antibody-positive early rheumatoid arthritis in northern Sweden

The PTPN22 1858C/T polymorphism has been associated with several autoimmune diseases including rheumatoid arthritis (RA). We have shown that carriage of the T variant (CT or TT) of PTPN22 in combination with anti-cyclic citrullinated peptide (anti-CCP) antibodies highly increases the odds ratio for developing RA. In the present study we analysed the association between the PTPN22 1858C/T polymorphism and early RA in patients from northern Sweden, related the polymorphism to autoantibodies and the HLA-DR shared epitope, and analysed their association with markers for disease activity and progression. The inception cohort includes individuals who also donated samples before disease onset. A case–control study was performed in patients (n = 505; 342 females and 163 males) with early RA (mean duration of symptoms = 6.3 months) and in population-based matched controls (n = 970) from northern Sweden. Genotyping of the PTPN22 1858C/T polymorphism was performed using a TaqMan instrument. HLA-shared epitope alleles were identified using PCR sequence-specific primers. Anti-CCP2 antibodies were determined using enzyme-linked immunoassays. Disease activity (that is, the number of swollen and tender joints, the global visual analogue scale, and the erythrocyte sedimentation rate) was followed on a regular basis (that is, at baseline and after 6, 12, 18 and 24 months). Both the 1858T allele and the carriage of T were associated with RA (χ² = 23.84, P = 0.000001, odds ratio = 1.69, 95% confidence interval = 1.36–2.11; and χ² = 22.68, P = 0.000002, odds ratio = 1.79, 95% confidence interval = 1.40–2.29, respectively). Association of the 1858T variant with RA was confined to seropositive disease. Carriage of 1858T and the presence of anti-CCP antibodies was independently associated with disease onset at an earlier age (P < 0.05 and P < 0.01, respectively), while the combination of both resulted in an even earlier age at onset. Smoking was identified as a risk factor independent of the 1858T variant and anti-CCP antibodies.