TSHR is the main causative locus in autosomal recessively inherited thyroid dysgenesis

Research output: Contribution to journalArticle

Authors

  • Zehra Aycan
  • Halil Saglam
  • Julia R Forman
  • Semra Cetinkaya
  • Omer Tarim
  • Ece Bober
  • Yasar Cesur
  • Selim Kurtoglu
  • Feyza Darendeliler
  • Veysel Bas
  • Erdal Eren
  • Korcan Demir
  • Aslihan Kiraz
  • Banu K Aydin
  • Ambika Karthikeyan
  • Michaela Kendall
  • Nick J Shaw
  • Jeremy Kirk
  • Wolfgang Hogler

Abstract

Congenital hypothyroidism (CH) is the most common neonatal endocrine disorder and results in mental retardation if untreated. Eighty-five percent of CH cases are due to disruptions in thyroid organogenesis and are mostly sporadic, but about 2% of thyroid dysgenesis is familial, indicating the involvement of genetic factors in the aetiology of the disease. In this study, we aimed to investigate the Mendelian (single-gene) causes of non-syndromic and non-goitrous congenital hypothyroidism (CHNG) in consanguineous or multi-case families. Here we report the results of the second part (n=105) of our large cohort (n=244), representing the largest such cohort in the literature, and interpret the overall results of the whole cohort. Additionally, 50 sporadic cases with thyroid dysgenesis and 400 unaffected control subjects were included in the study. In familial cases, first, we performed potential linkage analysis of four known genes causing CHNG (TSHR, PAX8, TSHB, and NKX2-5) using microsatellite markers and then examined the presence of mutations in these genes by direct sequencing. In addition, in silico analyses of the predicted structural effects of TSHR mutations were performed and related to the mutation specific disease phenotype. We detected eight new TSHR mutations and a PAX8 mutation but no mutations in TSHB and NKX2-5. None of the biallelic TSHR mutations detected in familial cases were present in the cohort of 50 sporadic cases. Genotype/phenotype relationships were established between TSHR mutations and resulting clinical presentations. Here we conclude that TSHR mutations are the main detectable cause of autosomal recessively inherited thyroid dysgenesis. We also outline a new genetic testing strategy for the investigation of suspected autosomal recessive non-goitrous CH.

Details

Original languageEnglish
Pages (from-to)419-426
Number of pages8
JournalJournal of pediatric endocrinology & metabolism
Volume25
Issue number5-6
Early online date24 May 2012
Publication statusPublished - Jun 2012