Polymorphisms associated with type 1 diabetes mellitus

Abstract

Background Type 1 diabetes mellitus (T1DM) is an organ-specific autoimmune disease characterized by T cell-mediated destruction of pancreatic islets. The genetic factors involved consist of at least five vulnerability genes: HLA, INS, CTLA-4, PTPN22, and IL2RA/CD25.
 Objective To investigate for associations of PTPN22-1123 G>C SNP and CTLA-4 +49A/G polymorphisms with T1DM.
 Methods Case and control groups underwent CTLA-4 +49A/G gene examination from June to December 2017, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis.
 Results The study population consisted of 30 T1DM patients and 30 healthy subjects with no family history of diabetes or autoimmune diseases. With regards to the PTPN22-1123 G>C SNP, significantly more subjects with T1DM had the GC genotype than the GG genotype (OR 7.64; 95%CI 1.48 to 39.29; P=0.007). For the CTLA-4 +49A/G polymorphism, although the total number of G alleles in the case group was more than that of the control group (OR 2.286; 95%CI 0.804 to 6.945; P=0.118), there were no significant relationships between the frequency of G alleles (P=0.248) and genotypes GG or AG (P=0.293) with the incidence of T1DM. However, the PTPN22-1123 G>C SNP had a significantly positive association with T1DM, and may be considered as a risk factor for T1DM. In contrast, the CTLA-4 +49A/G polymorphism was not recognized as a risk susceptibility factor for T1DM.
 Conclusion These study confirms an association between PTPN22-1123 G>C SNP and T1DM, but no significant association between CTLA-4 +49A/G polymorphism and T1DM.

CTLA-4 CT-60 A/G and CTLA-4 1822 C/T Gene Polymorphisms in Indonesians with Type 1 Diabetes Mellitus

“…A study in Palembang reported the CTLA-4 49 A/G gene polymorphism to be prevalent in 36% T1Dof M subjects; the frequency of G and encylele was 71.6%. 24 Unlike our study, Tanhapour et al showed that the correlation between CTLA-4 CT60 A/G polymorphism and autoimmune disorders is inconclusive. 20 …”

“…The frequency of polymorphism of CTLA-4 49 A/G in Palembang ethnic was 46.7%. 24 A significant risk of CTLA-4 49 A/G, otherwise reported in the Indian and African populations, has been reported in the Middle East and Caucasian populations. 20 …”

“… 22 The frequency of CTLA-4 49 A/G gene polymorphism and G allele in the Chinese population has been reported to be 33.6% and 76.1%, respectively. 24 …”

The association between PTPN22 C1858T gene polymorphism and type 1 diabetes mellitus: an Indonesian study

“…There are various causes of T1DM, such as genetic risk factors including β-pancreatic cell destruction induced by T-cell [ 2 , 11 , 12 ]. In 2008, Ikegami et al.…”

“…There have been reports of the 1858T allele being linked to T1DM in several countries, including Italy, Germany, Spain, Ukraine and France [ 13 ]. This topic has been studied since 12 years ago [ 12 , 17 , 18 ]. However, PTPN22 studies in Indonesia is limited.…”