Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
Mothers with the 677C-->T mutation had a 2.6-fold higher risk of having a child with Down syndrome than did mothers without the T substitution (odds ratio: 2.6; 95% CI: 1.2, 5.8; P < 0.03).
|
10500018 |
1999 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
The results are consistent with the preliminary observation that the MTHFR 677C-->T polymorphism is more prevalent among mothers of children with Down syndrome than among control mothers, with an odds ratio of 1.91 (95% confidence interval [CI] 1.19-3.05).
|
10930360 |
2000 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
In the present report, we asked whether variation at MTHFR (677C-->T) or MTRR (66A-->G) might be associated with human trisomies other than trisomy 21.
|
11443546 |
2001 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
MTHFR C677T genotype frequencies were not significantly altered in mothers of children with Down syndrome (P = 0.74).
|
11807890 |
2002 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
C677T mutation in the 5,10-MTHFR gene and risk of Down syndrome in Italy.
|
12080391 |
2002 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
Recent studies have linked the increased frequency of polymorphism of methylenetetrahydrofolate reductase (MTHFR, C677T) and methionine synthase gene (MTRR, A66G) in mothers with DS child.
|
12626825 |
2003 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
Contradictory findings have been recently published on the evaluation of genetic polymorphisms of methylenetetrahydrofolate reductase (MTHFR 677 C-->T) and methionine synthase reductase (MTRR 66 A-->G) as risk factors for having a child with Down syndrome (DS); however, the influence of polymorphisms of methionine synthase (MTR 2756 A-->G) and of MTHFR 1298 A-->C has never been evaluated.
|
12923861 |
2003 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
In contrast, MTHFR 677 C --> T has no influence on DS risk in France and Sicily, while homocysteine and MTR 2756 AG/GG genotypes are predictors of DS risk in Sicily.
|
14656028 |
2003 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
This is yet the largest case-control study conducted for MTHFR 677C > T and also the first to investigate a possible relation with MTHFR 1298A > C. The data presented in this study fail to support the relationship between MTHFR 677C > T and 1298A > C polymorphisms and risk of having a child with DS.
|
15103709 |
2004 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
In the present study, we determined polymorphisms of MTHFR A222V (677C > T), MTHFR E429A (1298A > C), MTRR I22M (66A > G), MTR D919G (2756A > G), and CBS 844ins68 and total plasma homocysteine levels (tHcy) among 154 mothers of children with Down syndrome (DS) and 158 control mothers from Brazil.
|
15889417 |
2005 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
Present results seem to indicate that none of the RFC-1 80G>A, MTHFR 677C>T, and MTHFR 1298A>C polymorphisms is an independent risk factor for a DS offspring at a young maternal age; however, a role for the combined MTHFR/RFC-1 genotypes in the risk of DS pregnancies among young Italian women cannot be excluded.
|
16596679 |
2006 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
This study was aimed at analyzing the effect of mutations in three non-synonymous SNP genes (677C > T and 1298A > C of the methylenetetrahydrofolate reductase (MTHFR) gene, and 66A > G in the MTRR gene) on total plasmatic homocysteine (Hcy), in 91 mothers of Down syndrome (DS) infants and 90 control mothers.
|
16575899 |
2006 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
(Am J Med Genet 103:128-132, 2001) found the homozygous 677T allele of the methylenetetrahydrofolate (MTHFR) gene 677C-->T polymorphism in a mother and her child with DS and cervical meningomyelocele.
|
16602006 |
2006 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
Significant association with both of these SNPs were detected, more specifically, in the mothers of DS children homozygous for the polymorphic alleles 677 T and 1298 C. The relative risk of T (C677T) and C (A1298C) homozygosity in mothers for DS-affected pregnancy was 7 (OR 7.67, 95% CI 1.67-35.08, P=0.003) and 4 (OR 4.40, 95% CI 1.45-13.26, P=0.008), respectively.
|
16489479 |
2006 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
A meta-analysis of 11 case-control studies relating MTHFR C677T, MTHFR A1298C and MTRR A66G gene polymorphisms to the maternal risk of DS was carried out.
|
17934692 |
2007 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
The aim of the present study was to evaluate chromosome damage, measured by means of the micronucleus assay, in peripheral lymphocytes of a group of women (n = 34) who had a DS child in young age (<35 years) and in a control group (n = 35), and to correlate them with MTHFR 677C > T and 1298A > C, RFC-1 80G > A and MTR 2756A > G polymorphisms.
|
17702010 |
2007 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
With the purpose of evaluating this relationship, we compared the frequencies of 677C>T and 1298A>C polymorphisms in the methylenetetrahydrofolate reductase gene (MTHFR) and 66A>G in the methionine synthase reductase gene (MTRR) between 103 young mothers of Down syndrome (DS) individuals and 108 control mothers, whose offspring was karyotypically normal, correlating it with an estimative of folate and - related micronutrients levels intake.
|
19096127 |
2008 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
The aim of the present study was to investigate the effect of polymorphisms C677T and A1298C in the methylenetetrahydrofolate reductase (MTHFR) gene, A2756G in methionine synthase reductase (MTR) gene and A80G in reduced folate carrier 1 (RFC1) gene, and plasma homocysteine (Hcy), on the maternal risk for Down syndrome (DS).
|
18273817 |
2008 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
The authors have conducted a study to test whether 677C-->T and/or 1298A-->C polymorphisms of MTHFR would play an additional role in susceptibility of acute myeloid leukemia (AML) in DS children.
|
19065440 |
2008 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
The present study aimed at evaluation of MTHFR 677C/T and 1298A/C polymorphisms in the MTHFR gene as maternal risk factors for DS.
|
18057532 |
2008 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
The results show that the MTHFR 677C-->T polymorphism is more prevalent among mothers of children with Down syndrome than among control mothers, with an odds ratio of 3.78 (95% confidence interval (CI), 1.78 approximately 8.47).
|
18257130 |
2008 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
We conclude that the common MTHFR 677C>T polymorphism is not likely to be a maternal risk factor for DS in our cohort and that the difference to previous studies can probably be explained by small sample size or geographic variation in gene polymorphisms involving gene-nutritional or gene-gene or gene-nutritional-environmental factors.
|
20075510 |
2009 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
Evaluation of C677T and A1298C polymorphisms of the MTHFR gene as maternal risk factors for Down syndrome and congenital heart defects.
|
19725133 |
2009 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
Understanding the biochemical structure and function of the methylenetetrahydrofolate reductase gene (MTHFR) provides new evidence in elucidating the risk of having a child with Down syndrome (DS) in association with two common MTHFR polymorphisms, C677T and A1298C.
|
20592453 |
2010 |
Down Syndrome
|
|
0.100 |
GeneticVariation
|
BEFREE |
This study aimed to analyze a dataset of genetic and cytogenetic data in an Italian group of MDS and mothers of healthy children (control mothers) to assess the predictive capacity of artificial neural networks assembled in TWIST system in distinguish consistently these two different conditions and to identify the variables expressing the maximal amount of relevant information to the condition of being mother of a DS child.The dataset consisted of the following variables: the frequency of chromosome damage in peripheral lymphocytes (BNMN frequency) and the genotype for 7 common polymorphisms in folate metabolic genes (MTHFR 677C>T and 1298A>C, MTRR 66A>G, MTR 2756A>G, RFC1 80G>A and TYMS 28bp repeats and 1494 6bp deletion).
|
20868477 |
2010 |