Abstract |
Allan-Herndon-Dudley syndrome (AHDS), an X linked condition, is characterized by severe intellectual disability, dysarthria, athetoid movements, muscle hypoplasia and spastic paraplegia in combination with altered TH levels, in particular, high serum T3 levels. Mutations in the MCT8 gene coding for the monocarboxylate thyroid hormone transporter 8 have been associated with AHDS. Here we describe a family with the presence of a MCT8 gene mutation, p.A224T, in three consecutive generations. In two generations its presence was detected in the hemizygous state in two males with neurological abnormalities including mental retardation, axial hypotonia, hypertonia of arms and legs and athetoid movements. One of them presented normal thyroid hormone levels. Mutation was also detected, although in the heterozygous state, in three females showing thyroid hormone levels in the normal range. Our results show the difficulty of distinguishing AHDS from patients with X-linked intellectual disability solely on the basis of clinical features and biochemical tests, and we advise screening for MCT8 mutations in either young or older patients with severe intellectual disability, axial hypotonia/ dystonia, poor head control, spastic paraplegia, and athetoid movements even when they have normal thyroid hormone profiles.
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Authors | Loredana Boccone, Valentina Dessì, Antonella Meloni, Georgios Loudianos |
Journal | European journal of medical genetics
(Eur J Med Genet)
Vol. 56
Issue 4
Pg. 207-10
(Apr 2013)
ISSN: 1878-0849 [Electronic] Netherlands |
PMID | 23419639
(Publication Type: Journal Article)
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Copyright | Copyright © 2013 Elsevier Masson SAS. All rights reserved. |
Chemical References |
- Monocarboxylic Acid Transporters
- SLC16A2 protein, human
- Symporters
- Triiodothyronine
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Topics |
- Adult
- Child
- Female
- Heterozygote
- Humans
- Infant
- Male
- Mental Retardation, X-Linked
(diagnosis, genetics)
- Middle Aged
- Monocarboxylic Acid Transporters
(genetics)
- Muscle Hypotonia
(diagnosis, genetics)
- Muscular Atrophy
(diagnosis, genetics)
- Mutation, Missense
- Pedigree
- Phenotype
- Symporters
- Triiodothyronine
(blood)
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