ESPE Abstracts

Background: Down Syndrome (DS) patients have a higher incidence of primary hypothyroidism. We previously demonstrated that transgenic mice overexpressing Dyrk1A had developmental (larger primary thyroids at E15.5 stage of development), morphological (disorganized follicles) and functional (significant lower plasma T4) impairments similar to DS thyroidal impairments (Endocrinology 2015). DYRK1A, localized in the DS critical region on chromosome 21, is therefore the can...

Congenital hypothyroidism from thyroid dysgenesis (CHTD) is mainly a sporadic and non-syndromic condition occurring in 1:4,500 live births. In contrast to rare cases of syndromic monogenic CHTD, non-syndromic (NS) CHTD shows low familial recurrence risk (~2%) and low concordance rate between MZ twins, suggesting a two-hit scenario combining post-zygotic events with either a de novo monogenic mutation or incomplete penetrance of polygenic inherited variants,. As this l...

Background: Brain-Lung-Thyroid (BLT) syndrome (OMIM# 610978) is characterized by congenital hypothyroidism (CH), infant respiratory distress syndrome (IRDS), and benign hereditary chorea and is caused by thyroid transcription factor 1 (NKX2-1/TTF1) haploinsufficiency. The phenotype can be partial or complete and there is a large phenotypic variability.Objectives and hypotheses: Identify new genes in a selected group of patients presenting thyroi...

Background: Congenital hypothyroidism (CH) affects one in 3000 children at birth. In 65% of cases, CH is due to thyroid dysgenesis (CHDT). For CHDT, there is a family component and therefore genetic. Over the past 20 years, disease-causing mutations in 10 genes have been implicated in CHDT cases (NKX2-1/TTF1, FOXE1/TTF2, NKX2-5, PAX8, GLIS3, NTN1/Netrin-1, JAG1, BOREALIN/CDCA8, TUBB1</...

Background: We found BOREALIN/CDCA8 mutations in patients with Congenital Hypothyroidism and Thyroid Dysgenesis, varying from asymmetric lobes to athyreosis (Carré et al. Hum Mol Genet 2017). Borealin is a major component of the Chromosomal Passenger Complex, an essential regulator of mitosis. We demonstrated a new feature of BOREALIN: involvement in the adhesion and the migration of the thyrocytes.<strong...

Background: Congenital hypothyroidism is primarily due to thyroid dysgenesis (TD). The genes implicated in TD, account for a small number of patients with monogenic forms, less than 5%. Borealin is a major component of the Chromosomal Passenger Complex, an essential regulator of mitosis.Objective and hypotheses: To understand the role of Borealin mutations found in patients with TD.Method: We performed whole exome sequencing (WES) ...

Background: Congenital hypothyroidism (CH) is the most common neonatal endocrine disorder, with an incidence of 1:3000 neonates, and one of the most frequent preventable causes of mental retardation worldwide. Most (65%) cases of primary permanent CH are due to thyroid dysgenesis (TD). However, a genetic cause is identified in less than 5% of CH due to DT.Methods: We performed WES (Whole Exome Sequencing) for siblings with childhood-onset TD and we analy...