ArticleJournal of neurology, neurosurgery, and psychiatry2005
Homocysteine and related genetic polymorphisms in Down's syndrome IQ.
Article in Journal of neurology, neurosurgery, and psychiatry, 2005. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 19 papers.
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Who cites it
19 citing papers in PubMed.
- Thyroid hormone and folinic acid in young children with Down syndrome: the phase 3 ACTHYF trial.Genetics in medicine : official journal of the American College of Medical Genetics · 2020Trial
- Trial
- Down Syndrome: From Pregnancy through Childhood in Türkiye.Molecular syndromology · 2026Article
- Role of cystathionine-β-synthase and hydrogen sulfide in down syndrome.Neurotherapeutics : the journal of the American Society for Experimental NeuroTherapeutics · 2025Review
- Article
- From neurodevelopment to neurodegeneration: utilizing human stem cell models to gain insight into Down syndrome.Frontiers in genetics · 2023Review
- Shaking up the silence: consequences of HMGN1 antagonizing PRC2 in the Down syndrome brain.Epigenetics & chromatin · 2022Review
- Neurodevelopment in Down syndrome: Concordance in humans and models.Frontiers in cellular neuroscience · 2022Review
- One-carbon pathway and cognitive skills in children with Down syndrome.Scientific reports · 2021Article
- Sonic Hedgehog Pathway Modulation Normalizes Expression of Olig2 in Rostrally Patterned NPCs With Trisomy 21.Frontiers in cellular neuroscience · 2021Article
- Combined effect of polymorphisms of MTHFR and MTR and arsenic methylation capacity on developmental delay in preschool children in Taiwan.Archives of toxicology · 2020Observational
- A pilot study on the contribution of folate gene variants in the cognitive function of ADHD probands.Neurochemical research · 2014Article
- Methylenetetrahydrofolate reductase polymorphism is not risk factor for Down syndrome in North India.Indian journal of human genetics · 2014Article
- DHFR 19-bp deletion and SHMT C1420T polymorphisms and metabolite concentrations of the folate pathway in individuals with Down syndrome.Genetic testing and molecular biomarkers · 2013Article
- A functional variant in the cystathionine β-synthase gene promoter significantly reduces congenital heart disease susceptibility in a Han Chinese population.Cell research · 2013Article
- S phase entry causes homocysteine-induced death while ataxia telangiectasia and Rad3 related protein functions anti-apoptotically to protect neurons.Brain : a journal of neurology · 2010Article
- Early incidence of occupational asthma among young bakers, pastry-makers and hairdressers: design of a retrospective cohort study.BMC public health · 2010Article
- Gestational vitamin B deficiency leads to homocysteine-associated brain apoptosis and alters neurobehavioral development in rats.The American journal of pathology · 2007Article
- Plasma amino acids and neopterin in healthy persons with Down's syndrome.Journal of neural transmission (Vienna, Austria : 1996) · 2007Article
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Authors and funding
8 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
objectiveDown's syndrome (DS) is the most frequent genetic cause of Alzheimer-type dementia. Its metabolic phenotype involves an increased trans-sulphuration of homocysteine. The aim of the present study was to investigate the influence of homocysteinaemia (t-Hcys), folate, vitamin B(12), and related polymorphisms on intelligence quotient (IQ) in DS.
methodsThe IQ of 131 patients with trisomy 21 from a specialist centre in Sicily was determined and classified according to DMS-IV. The effects of age, folate, vitamin B(12), t-Hcys, and genetic polymorphisms on IQ were evaluated separately and in combination using regression analyses.
resultsIQ was significantly lower in DS patients with t-Hcys >7.5 micromol/l (median) and in those who were carriers of methylenetetrahydrofolate reductase (MTHFR) 677 T allele and of methylenetetrahydrofolate reductase 677 T and transcobalamin 776 G combined alleles (p = 0.0013, p = 0.0165, and p = 0.0074, respectively). The IQ correlated significantly with t-Hcys and folate in single and multiple regression analyses, independently of age. In addition, t-Hcys >9.6 micromol/l (upper quartile) was found to be associated with low IQ (<40, median of study group) with an odds ratio of 2.61 (p = 0.0203). The odds ratio was increased by threefold in carriers of MTHFR 677T allele. The MTHFR 677T allele/transcobalamin 776 G allele combination was associated with the risk of DS patients to have an IQ less that the median with an odds ratio of 2.68 (95% CI 1.26 to 5.70, p = 0.0104).
conclusionThis study found evidence of an association between t-Hcys and MTHFR 677 T and transcobalamin 776 G alleles with IQ in patients with DS. The association may be related to a defective remethylation of homocysteine, affecting IQ.
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