Major effects of two SNPs, C1167T (rs769217) and C(-262)T (rs1001179), of the catalase gene on T1D susceptibility have been reported previously in Russians from Moscow.
The nucleotide substitutions in exon 4 in the patient with type 1 diabetes and that with fibrocalculous pancreatopathy occurred at codons 103 and 84 while that in exon 5 in the patient with type 1 diabetes occurred at codon 141, changing the codons from CAT to CAC, GTG to GCG, and ACT to AAT and resulting in H103H silent, V84A and T141N missense mutations, respectively.