Identifying SNPs from GWAS Associated with Type 1 Diabetes—A Meta-Analysis

Type 1 diabetes mellitus (T1D) is a common autoimmune disease during childhood with a substantial genetic component. Individual genome-wide association studies (GWAS) often have limited power and are predominantly based on European-ancestry populations. To provide a more robust synthesis of genetic associations, we conducted a meta-analysis using summary-level GWAS data from three independent pediatric T1D studies obtained from the NHGRI-EBI GWAS Catalog. Harmonized single-nucleotide polymorphisms (SNPs) shared across all datasets were analyzed using inverse-variance weighted fixed-effects and random-effects models, with between-study heterogeneity assessed using Cochran’s Q test and the I2 statistic. Of the 4,297,702 million common SNPs analyzed, 3524 reached genome-wide significance (p<5×10−8), demonstrating strong and consistent associations with T1D risk. The most prominent signals clustered on chromosome 6, consistent with known immune-related loci, and included both risk-increasing and protective variants, in agreement with prior biological findings. Heterogeneity across studies was minimal, with I2 values near 0% for nearly all SNPs. These findings highlight robust and reproducible SNP-level associations with pediatric T1D, providing an updated foundation for functional follow-up and translational studies.