ESPE Abstracts

Background: Pathogenic variants in the genes involved in the formation of thyroid tissue and thyroid hormone secretion have been reported to cause congenital hypothyroidism (CH) in some cases.

Aim: This study aimed to evaluate the clinical and genetic findings of CH cases thought to be due to genetic variants

Method: The study included cases whose genetic analysis was performed in accordance with the Congenital Hypothyroidism: A 2020–2021 Consensus Guidelines Update Guidelines recommendations criteria and analyzed them using the next-generation sequencing panel.

Results: 61 Turkish patients from 45 families were included in the study. The overall frequency of variant detection was 37.7% (26 cases from 17 families). Variants in the TPO gene are the most frequently encountered, a situation that was identified in 10 families. This was followed by variants in the TSHR gene in 7 families, variants in the DUOX2 gene in 5 families, and 2 variants in the TG and NKX2-1 genes in 2 families each, which are 6 novel variants.

Conclusion: In the current investigation, rare new variations in genes known to be related to CH were discovered, adding to the molecular genetic spectrum. When we compare the overall variant detection frequency, the selection criterion for genetic analysis based on the current guidelines is quite rational, considering the benefits and costs, on the other hand, present in new genes awaiting discovery. Also, TSHR mutations are likely to be common and may account for more than 5% of TD cases if we include non-familial thyroid dysgenesis.