Endocrine Abstracts

Corepressors and coactivators mediate thyroid hormone receptor-dependent repression and transactivation of positively-regulated target genes respectively, but their role in negative regulation is not understood.A 4 years old boy was born at 31 weeks. He was jittery at birth, with neonatal respiratory distress. Childhood features included poor weight gain, heat intolerance, tachycardia and hyperactivity. Ongoing problems are low frequency hearing loss, po...

The superfamily of ~25 human selenoproteins includes antioxidant and oxidoreductase enzymes together with other proteins of unknown function. We describe a child with a multisystem disorder involving deficiencies of several selenoproteins, identified on the basis of abnormal thyroid function.A 3.6-year-old male was referred with elevated free thyroxine (FT4 – 44.4 pmol/l (N 12–22)), low free triiodothyronine (FT3 &#...

Previously we reported two loss-of-function dominant negative mutations (P467L, V290M) in human peroxisome proliferator-activated receptor gamma (PPARg) in three individuals with severe insulin resistance, early onset type 2 diabetes mellitus (T2DM) and hypertension. Subsequent detailed clinical and radiological evaluation of these subjects has revealed that each exhibits a stereotyped pattern of partial lipodystrophy affecting the limbs and buttocks. Recently a female with pa...

We have previously reported dominant negative missense mutations (P467L, V290M) in human PPAR gamma (peroxisome proliferator-activated receptor gamma) in association with severe insulin resistance, early onset type 2 diabetes and hypertension. In a large UK kindred, where the proband presented at age 15 years with severe insulin resistance (acanthosis nigricans, hyperinsulinaemia, PCOS), we have identified a novel heterozygous frameshift premature stop mutation in the PPAR gam...

The nuclear receptor PPARgamma is important for biological processes including adipogenesis and glucose homeostasis. In subjects with severe insulin resistance, we have previously reported two types of human PPARgamma gene defect: heterozygous, missense mutations (P467L, V290M) in the ligand binding domain (LBD) which inhibit wild type (WT) receptor action in a dominant negative manner by recruitment of transcriptional corepressors; or double heterozygosity for a frameshift/pr...

Introduction: Thyroid hormones act via receptors encoded by different genes (THRA and THRB) generating receptor subtypes (TRα1, TRβ1, TRβ2) with differing, tissue-specific expression. Resistance to Thyroid Hormone due to THRB defects is well recognised, but no THRA mutations have yet been reported. We describe the first case of human TRα-mediated thyroid hormone resistance due to a dominant negative THRA mutation.Results: A 6-year-old...