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

Abstract

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.

PTPN22 Gene Polymorphism (C1858T) Is Associated with Susceptibility to Type 1 Diabetes: A Meta‐Analysis of 19,495 Cases and 25,341 Controls

“…Genotype distributions in the controls of all studies were in agreement with HWE, except for a study in the female subgroup (Saccucci et al, 2008).…”

“…However, after reading the full articles and contacting the authors, we excluded three meta-analysis studies (Lee et al, 2007;Peng et al, 2012;Tang et al, 2012), one study that had only case data (Maier et al, 2006), one duplicate study , four familybased research studies (Ladner et al, 2005;Qu et al, 2005;Onengut-Gumuscu et al, 2006;Steck, Baschal et al, 2009), and seven studies (Aarnisalo et al, 2008;Bjornvold et al, 2008;Zoledziewska et al, 2008;Lempainen et al, 2009;Steck, Zhang et al, 2009;Maziarz et al, 2010;Plagnol et al, 2011) in which information could not be obtained after authors were contacted. Finally, 28 studies (30 cohorts) (Bottini et al, 2004;Smyth et al, 2004;Gomez et al, 2005;Kahles et al, 2005;Zheng & She, 2005;Zhernakova et al, 2005;Fedetz et al, 2006;Hermann et al, 2006;Steck et al, 2006;Chelala et al, 2007;Cinek et al, 2007;Nielsen et al, 2007;Santiago et al, 2007;Baniasadi & Das, 2008;Cervin et al, 2008;Douroudis et al, 2008;Petrone et al, 2008;Saccucci et al, 2008;Dultz et al, 2009;Korolija et al, 2009;Chagastelles et al, 2010;Fichna et al, 2010;Klinker et al, 2010;Kordonou...…”

“…In this stratified analysis, except for one South Asian study (Baniasadi & Das, 2008), 27 different studies (29 cohorts), consisting of 19,366 cases and 25,232 controls with specific focus on the Caucasian population, were included in ethnic groups. In another stratified analysis, seven studies (Kahles et al, 2005;Nielsen et al, 2007;Santiago et al, 2007;Cervin et al, 2008;Saccucci et al, 2008;Klinker et al, 2010) on the Caucasian population were included in gender-specific groups. The main characteristics of the included studies are listed in Table 1.…”

“…3), suggesting that the results of this meta-analysis were stable. In addition, we removed the study by Saccucci and coworkers (Saccucci et al, 2008) in the stratified analysis due to the genotype distribution in the control groups of the study slightly deviating from HWE. We found that the corresponding pooled ORs were not substantially altered in the female Caucasian population (data not shown).…”

The role of common genetic markers in susceptibility to type 1 diabetes and autoimmune thyroid diseases

“…Saccucci с соавт. [113] первыми установили связь между СД1 и вариан-том R620W гена PTPN22 на двух популяциях итальянцев с СД1. Дальнейшими исследованиями было показано, что аллель W была связана с подгруппой пациентов с СД1, пострадавших от другого аутоиммунного заболевания, в частности, от АИТ, но не от целиакии [113].…”