Prevalence of Islet Autoantibodies in Type 1 Diabetes

Differential HLA Association of GAD65 and IA2 Autoantibodies in North Indian Type 1 Diabetes Patients

The human leucocyte antigen (HLA) association with type 1 diabetes (T1D) is well known but there are limited studies investigating the association between β-cell autoantibodies and HLA genes. We evaluated the prevalence of GAD65 and IA-2 autoantibodies (GADA and IA2A) in 252 T1D patients from North India and investigated the genetic association of GADA and IA2A with HLA class I and class II genes/haplotypes. GADA and IA2A were detected in 50.79% and 15.87% of T1D patients, respectively, while only 8.73% had both GADA and IA2A. HLA-DRB1^∗03 was observed to be significantly higher in GADA+ T1D patients as compared to GADA- (91.41% vs. 66.13%, Bonferroni-corrected P (P _c) = 1.11 × 10^-5; OR = 5.45; 95% CI: 2.67-11.08). Similarly, HLA-DQB1^∗02 was found to be significantly increased in GADA+ patients (94.53%, P _c = 2.19 × 10^-5; OR = 6.27; 95% CI: 2.7-14.49) as compared to GADA- (73.39%). The frequencies of HLA-DRB1^∗04 and DQB1^∗03 were increased in IA2A+ patients (45.0% and 52.5%, respectively) as compared to that in IA2A- (25.94% and 33.96%, respectively). Further, the frequency of DRB1^∗03-DQB1^∗02 haplotype was found to be significantly increased in GADA+ T1D patients as compared to GADA- (60.55% vs. 41.94%, P = 3.94 × 10^-5; OR = 2.13; 95%CI = 1.49-3.03). Similarly, HLA-DRB1^∗04-DQB1^∗03 haplotype was found to be significantly increased in IA2A+ T1D patients compared to IA2A- patients (22.5% vs. 12.97%; P = 0.041; OR = 1.95; 95%CI = 1.08-3.52). None of the HLA class I genes (HLA-A, B, and Cw) was found to be associated with GADA or IA2A in people with T1D. Our findings suggest that HLA-DRB1^∗03/DQB1^∗02 and HLA-DRB1^∗04/DQB1^∗03 might play an important role in the development of GADA and IA2A, respectively.

Lissencephaly-pachygyria spectrum in a North Indian boy with Wolcott-Rallison syndrome due to homozygous deletion of exon 1 in the EIF2AK3 gene

BACKGROUND

Wolcott-Rallison syndrome (WRS) is a rare autosomal recessive disorder characterized by neonatal diabetes mellitus (NDM), epiphyseal dysplasia, and hepatic and renal dysfunction. Although neuro-psychological features are common in patients with WRS, malformations of cortical development (MCDs) are rarely reported.

CASE PRESENTATION

A 3-month-old boy, born to non-consanguineous parents, presented with right focal seizures since two months of age and recently detected diabetes mellitus. He also had a small head and lissencephaly-pachygyria spectrum on brain imaging. Genetic testing confirmed the diagnosis of WRS by identifying a biallelic homozygous deletion of exon 1 in the EIF2AK3 gene. The child achieved reasonable glycemic control on the basal-bolus insulin regimen.

CONCLUSIONS

Presentation of WRS may occur with neurological manifestations such as lissencephaly-pachygyria spectrum. Early confirmation of the genetic diagnosis of WRS by screening for pathogenic variants in the EIF2AK3 gene is important in children with NDM and associated syndromic features. Establishing the diagnosis of WRS helps in predicting the development of subsequent clinical features, guides management, and may improve patient outcomes.