Molecular genetic and clinical variants MODY2 and MODY3 in children in Russia

Aim — to research molecular genetic and clinical characteristics of diabetes mellitus MODY2 and MODY3 in children.Material and methods. Genetic testing for GCK and HNF1α was performed in 169 patients with carbohydrate metabolism disorders, with age of diagnosis under 18. Carbohydrate metabolism disorders were interpreted as MODY. Analysis of clinical data at the presentation of carbohydrate metabolism disorder and cases follow-up was provided in 62 patients with genetic confirmed MODY2 and 18 patients with genetic confirmed MODY3.Results. Ratio MODY2 and MODY3 was 3,4:1. Carbohydrate metabolism disorders were diagnosed earlier in MODY2 than in MODY3 — 7,8 years (4,0; 10,5) vs. 11,8 years (9,7; 13,5) (p<0,01). Degree of carbohydrate metabolism disorder was less in MODY2 — in 22,4% of patients all makers of carbohydrate metabolism disorder (HbA1c, fasting glycaemia, 120 min glycaemia) were less than diabetic range, in MODY3 all these makers were diabetics in 100% of cases. Patients with MODY2 significantly less frequently were treated with antihyperglycemic drugs. Carbohydrate metabolism disorders in one of the parents were diagnosed earlier in MODY3 — in 24 years (18,5; 35,3) vs. 32 years (27; 37) in MODY2 (p<0,05), parents were treated with antihyperglycemic drugs — in 94,4% vs. 22,2%  respectively (p<0,01).Conclusion. This study is the largest in Russia and estimated that MODY2 is the most prevalence and has had milder presentation and less dysfunction of β-cells to compare to MODY-HNF1α.