Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0025362 (mental retardation)
 15,878 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

It is known that in the pathogenesis of mental retardation (MR), both genetic and environmental factors (particularly iodine deficiency) appear to play a critical role. Transthyretin (TTR) transports between 20% and 30% of serum thyroxine in normal individuals and it is the main T(4)-binding protein in CSF. Variability in the TTR gene may influence risk for iodine-deficiency-based MR. The SNPs we selected from dbSNP were detected and identified using ARMS-PCR and sequencing methods, and we identified five novel sequence variants. Singular-locus association analysis indicated no association between the TTR gene and MR. In haplotype analysis, however, we found a haplotype CGTG+ (rs723744/G+6649C/T+6690C/rs2276382/del9) showed a weak positive association with MR (chi(2) = 6.699, p = 0.035). Finally, we concluded that the weak positive result is more likely to be due to sampling error and the small size of this haplotype resulting from its relative low frequency. Our negative results provide no evidence that variants of TTR gene influence susceptibility to MR in the iodine-deficient areas of China and suggest that there may be a compensatory mechanism(s) in humans and mice, which work(s) to compensate the effect of mutation in the TTR gene on MR.
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PMID:An association study between the transthyretin (TTR) gene and mental retardation. 1636 27

It is generally considered that iodine deficiency is the single most common cause of preventable mental retardation (MR) and brain damage. The SLC26A4 gene is expressed at the apical surface of thyrocytes and its product forms an efficient iodide-trapping mechanism. To investigate whether variability in the SLC26A4 gene influences the risk of iodine-deficiency based MR, we undertook an association study between SLC26A4 and MR. Participants were recruited from a relatively isolated and traditionally iodine-deficient region with a high prevalence of MR. The SNPs we selected from the dbSNP and HapMap were identified using ARMS-PCR and sequencing methods. Singular-locus and haplotype association analysis indicated no association between the SLC26A4 gene and MR (p>0.05). The negative results suggest that the SLC26A4 gene has no measurable impact on iodine-deficiency based MR. In view of the characteristics of our samples, our study may provide a good reference for research into the transport features of pendrin in the thyrocyte apical surface.
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PMID:An association study of the SLC26A4 gene in children with mental retardation. 1942 84