CTLA4 and type 1 diabetes mellitus: In addition the study revealed T/T genotype at the IL2RA locus (rs7093069) and G/G genotype at the CTLA-4 locus (rs231775) to be statistically significantly more frequent in children with T1D (P < 0.001, OR = 8.50, 95%CI = 2.42–58.38, the power of the test 1, estimated effect size w equal to 1.000, with the total sample size n = 299 and P = 0.015, OR = 2.34, 95%CI = 1.17–4.84, the power of the test was 0.997, estimated effect size w was equal to 0.320, with the total sample size n = 304 respectively) (Figures 3, 7).