Background: Maturity-onset diabetes of the young (MODY) is a common form of monogenic diabetes. Fourteen genes have been identified, each leading to cause a different type of MODY. The aims of this study were to reveal both known and novel variants in MODY genes in patients with MODY using targeted next generation sequencing (NGS) and to present the genotype-phenotype correlations. Methods: Mutation analysis of MODY genes ( GCK , HNF1A , HNF4A , HNF1B , ABCC8 , INS and KCNJ11 ) was performed using targeted NGS in 106 patients with a clinical diagnosis of MODY. The variants were evaluated according to American College of Medical Genetics and Genomics (ACMG) Standards and Guidelines recommendations. Results: A total of 18 (17%) variants were revealed among all patients. Seven variants in GCK , six in HNF4A , four in HNF1A and one in ABCC8 genes were found. Eight of them were previously published and 10 of them were assessed as novel pathogenic or likely pathogenic variants. Conclusions: While the most frequent mutations are found in the HNF1A gene in the literature, most of the variants were found in the GCK gene in our patient group using the NGS method, which allows simultaneous analysis of multiple genes in a single panel.

SECISBP2 is an essential factor in selenoprotein synthesis and its mutations result in a multiorgan syndrome including abnormal thyroid hormone metabolism. A ten-year-old obese Turkish boy born to consanguineous parents presented with high T4, low T3, high rT3 and normal or slightly elevated TSH. He also had attention deficit disorder and muscle weakness but no delay in growth or bone age. Sequencing of genomic DNA revealed a novel c.800_801insA, p.K267Kfs*2 mutation, homozygous in the proband and heterozygous in both parents and his brother. Studies showed reduction in several selenoproteins in serum and fibroblasts.

Purpose: The aim of this study was to evaluate the relationship between keratoconus (KC) and interleukin-1β (IL1 β) (–511C>T) and interleukin-1 receptor antagonist (IL1RN) variable number of tandem repeat (VNTR) polymorphisms that are potentially associated in their genetic susceptibility to KC. Methods: A total of 121 patients with KC and 121 healthy individuals were enrolled. Blood samples with ethylenediamine tetraacetic acid were obtained, and IL1β (−511C>T) (rs16944) (polymerase chain reaction–restriction fragment length polymorphism method) and IL1RN VNTR polymorphisms (rs2234663) (polymerase chain reaction and agarose gel imaging) were investigated. Results: Genotype and allele distribution for IL1β (−511C>T) and IL1RN VNTR polymorphisms among the KC and healthy groups showed no difference (for all; P > 0.05). Conclusions: Because the genotype and allele frequency of both polymorphisms are identical, it is most likely that IL1β-511C>T and IL1RN VNTR polymorphisms do not play a role in the development of KC in the Turkish population.