0000000000949330
AUTHOR
Eckhard Korsch
Four new cases of congenital secondary hypothyroidism due to a splice site mutation in the thyrotropin-beta gene: Phenotypic variability and founder effect
WOS: 000223072400081 PubMed ID: 15292359 Isolated TSH deficiency is a rare cause of congenital hypothyroidism. We here report four children from two consanguineous Turkish families with isolated TSH deficiency. Affected children who were screened at newborn age had an unremarkable TSH result and a low serum TSH level at diagnosis. Age at diagnosis and clinical phenotype were variable. All affected children carried an identical homozygous splice site mutation (IVS2 + 5 Gdouble right arrowA) in the TSHbeta gene. This mutation leads to skipping of exon 2 and a loss of the translational start codon without ability to produce a TSH-like protein. However, using specific monoclonal antibodies, we …
Congenital hypothyroidism caused by new mutations in the thyroid oxidase 2 (THOX2) gene
Summary Objective Congenital primary hypothyroidism (CH) occurs in one of 4000 births and in 20% of the cases CH is due to a defect in thyroid hormonogenesis. Candidate genes were examined to determine the precise aetiology of suspected dyshormonogenesis in CH. Design The genes that code for thyroid peroxidase (TPO), pendrin (PDS), sodium iodide symporter (NIS) and thyroid oxidase 2 (THOX2) were sequenced directly from genomic DNA. Patients Two girls found to have CH in the neonatal screening programme and suspected of having thyroid dyshormonogenesis were investigated to identify their molecular defect. Results Patient A had a novel heterozygous 1 bp insertion in the THOX2 gene (ins602…