Correlations of language abnormalities with localization of mutations in the beta-thyroid hormone receptor in 13 kindreds with generalized resistance to thyroid hormone: identification of four new mutations.
J Clin Endocrinol Metab
; 75(4): 1039-45, 1992 Oct.
Article
em En
| MEDLINE
| ID: mdl-1400869
ABSTRACT
Generalized resistance to thyroid hormone is an inherited disease characterized by unresponsiveness of pituitary and peripheral tissues to thyroid hormone. Genetic analysis of several kindreds linked this syndrome to the gene for the beta-form of the thyroid hormone receptor, and this led to the subsequent identification of various mutations in the ligand-binding domain of this receptor. In this region we now have found 4 new point mutations with reduced T3-binding affinities from separate kindreds by direct sequencing of polymerase chain reaction products. Similar to previously studied kindreds, the reduction in T3 binding of these four kindreds ranged from 2.5- to 5-fold, indicating that these are not neutral polymorphisms. Furthermore, the pattern of inheritance of these 4 kindreds is familial in 2, sporadic in 1, and unknown in 1. To date, 20 distinct mutations have been identified, of which 18 are clustered in 2 distinct topographical regions 11 are within the tau i/dimerization subdomains of exon 9, and 7 are within the L2 subdomain of exon 10. The 4 newly identified mutations coupled to the 9 mutations our laboratory has previously identified provide new insights into the clinical aspects of generalized resistance to thyroid hormone. Kindreds with mutations in exon 9 compared with those in exon 10 have significantly more problems in language development, as manifested by articulation problems and/or wide discrepancies in verbal and performance IQs. Interestingly, marked variability in language deficiency as well as other clinical patterns were seen not only between kindreds but also within a kindred. Further identification and clinical correlations of new mutations will continue to enhance our understanding of the structure/function relationships and physiological role of the human thyroid hormone receptor.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Receptores dos Hormônios Tireóideos
/
Transtornos da Linguagem
/
Mutação
Tipo de estudo:
Diagnostic_studies
Limite:
Adolescent
/
Adult
/
Aged
/
Child
/
Child, preschool
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Revista:
J Clin Endocrinol Metab
Ano de publicação:
1992
Tipo de documento:
Article