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Maturity onset diabetes of the young (MODY) is characterized by noninsulin-dependent diabetes diagnosed before the age of 25 years with an autosomal dominant inheritance. Rare mutations in the hepatocyte nuclear factor-1-beta (HNF1B) gene produce a syndrome that resembles MODY. About half of patients diagnosed with MODY type 5 due to HNF1B variants, carry a whole gene deletion, known as 17q12 deletion syndrome. 17q12 deletion syndrome is a rare chromosomal anomaly and is typified by deletion of more than 15 genes, including HNF1B resulting in kidney abnormalities and renal cysts, a diabetes syndrome and neurodevelopmental or neuropsychiatric disorders. A 12-year-old girl was referred after high blood sugar was detected in the hospital where she presented with polyuria and polydipsia, which had persisted for one month. Her serum magnesium (Mg) level was low at 1.5 mg/dL (normal value 1.6-2.6) and glycated hemoglobin was 14% (normal value 3.6-5.8) concurrent with a c-peptide of 1.54 ng/mL (normal value 0.8-4). MODY5 was suspected but the NGS gene panel (ABCC8, BLK, CEL, GCK, HNF1A, HNF1B, HNF4A, INS, KCNJ11, KLF11, NEURODD1, PAX4, PDX1, RFX6, ZFP57, GLIS3, FOXP3, NEUROG3, G6PC2) did not identify any abnormality. During follow-up, her serum Mg remained low (1.2 mg/dL) together with elevated urinary Mg excretion at 172.5 mg/day. An HNF1B variant was again suspected in a patient with chronic hypomagnesemia with normal basal C peptide level. Abdominal computed tomography and magnetic resonance imaging revealed a 43 mm diameter, cystic lesion in the head of the pancreas, with agenesis of the pancreatic neck, trunk and tail. Genetic testing using a microarray analysis was subsequently performed and a heterozygous deletion at 17q12, including HNF1B, was detected. In case of clinical suspicion of HNF1B variants, further genetic examination using other techniques such as MLPA and CGH array may be required to detect the variant. This is because deletions and duplications may not be detected using next generation screening panel techniques.

Background: The COVID-19 pandemic has been a global health problem with high morbidity and mortality. In this study, it was aimed to compare the clinical and laboratory findings of patients diagnosed with type 1 diabetes(T1D) during the pandemic and after the pandemic. Method: This is a 30-month, single-center, cross-sectional study. Between October 2020 and December 2021 was defined as the pandemic period, and between January 2022 and March 2023 as the post-pandemic period. The clinical and laboratory parameters of the newly diagnosed T1D patients who applied in these two time periods were compared. Results: While 87 patients were diagnosed during the pandemic period, 86 patients were diagnosed during the post-pandemic period. The rate of male patients diagnosed during the pandemic period was significantly higher (56%, 36%, respectively, p=0.007). Anti-islet Cell antibody (ICA) positivity was statistically significantly higher in those diagnosed during the pandemic period. (52.6%, 18.6%, respectively, p0.05).C peptide levels were significantly lower in those diagnosed during the pandemic period (0.39±0.4, 0.63±0.6, respectively, p=0.021). Admissions with severe acidosis were more common during the pandemic than those admitted after the pandemic (29.9%, 16.3%, respectively, p=0.151). Conclusions: The numbers of children with T1D newly diagnosed in a secondary health center were similar during and after the pandemic. In the pandemic period, admissions with autoantibody positivity, low C-peptide and severe acidosis were more common.

Objective:The aim of this study was to investigate the molecular basis of maturity-onset diabetes of the young (MODY) by targeted-gene sequencing of 20 genes related to monogenic diabetes, estimate the frequency and describe the clinical characteristics of monogenic diabetes and MODY in the Trakya Region of Turkey.Methods:A panel of 20 monogenic diabetes related genes were screened in 61 cases. Illumina NextSeq550 system was used for sequencing. Pathogenicity of the variants were assessed by bioinformatics prediction software programs and segregation analyses.Results:In 29 (47.5%) cases, 31 pathogenic/likely pathogenic variants in the GCK, ABCC8, KCNJ11, HNF1A, HNF4A genes and in 11 (18%) cases, 14 variants of uncertain significance (VUS) in the GCK, RFX6, CEL, PDX1, KCNJ11, HNF1A, G6PC2, GLIS3 and KLF11 genes were identified. There were six different pathogenic/likely pathogenic variants and six different VUS which were novel.Conclusion:This is the first study including molecular studies of twenty monogenic diabetes genes in Turkish cases in the Trakya Region. The results showed that pathogenic variants in the GCK gene are the leading cause of MODY in our population. A high frequency of novel variants (32.4%-12/37) in the current study, suggests that multiple gene analysis provides accurate genetic diagnosis in MODY.