The diagnosis of MODY should be verified by molecular genetic analysis. Recently the introduction of next-generation sequencing, allowing simultaneous analysis of several candidate genes, greatly facilitates the diagnosis of monogenic diseases including MODY. In addition, the simultaneous analysis of several candidate genes allows to identify cases with digenic and oligogenic inheritance. In this work we present the first description of MODY cases with digenic and oligogenic inheritance in our country.Aim — to characterize MODY cases with digenic and oligogenic inheritance as defined by targeted next-generation sequencing.Material and methods. 256 subjects (age range, 0.3—25 yrs; males, n=149, females, n=107) were included in the study. The patients fulfilled the following MODY criteria: diabetes or intermediate hyperglycemia, absence of β-cell autoimmunity (ICA, GAD, IA2, IAA antibodies), preserved C-peptide secretion. Molecular genetic analysis was performed by next-generation sequencing using custom Ion Ampliseq gene panel and PGM semiconductor sequencer (Ion Torrent). All mutations were confirmed by Sanger sequencing.Results. 10 patients (8 probands, 1 sibling and 1 parent) showed digenic inheritance of MODY: 3 patients with combination of mutations in 2 candidate genes of MODY, 7 — in a candidate genes of MODY and another gene, associated with diabetes mellitus. In 1 case (sibling) showed oligogenic inheritance (mutations in GCK, HNF4A and INSR genes). Seven of the identified mutations were not previously described.Conclusion. Next-generation sequencing is useful in identifying of MODY cases with digenic and oligogenic inheritance, which is extremely important with potentially modifying effect on the phenotype.
Molecular genetic analysis of PKHD1 by next-generation sequencing in Czech families with autosomal recessive polycystic kidney disease