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A Robust Polymerase Chain Reaction-based Assay for Quantifying Cytosine-guanine-guanine Trinucleotide Repeats in Fragile X Mental Retardation-1 Gene
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Infant C677T MTHFR polymorphism and severe mental retardation

Gary M Shaw1, Laura Jelliffe-Pawlowski, Verne Nelson

  • 1California Birth Defects Monitoring Program, Berkeley, California 94710, USA. gsh@cbdmp.org

Birth Defects Research. Part A, Clinical and Molecular Teratology
|December 7, 2006
PubMed

Insights

Infants with the MTHFR gene TT genotype showed no increased risk of severe mental retardation overall. However, Hispanic children with TT or CT genotypes had a higher risk, suggesting a potential link to folate metabolism.

Area of Science:

  • Genetics and Developmental Biology
  • Neuroscience
  • Public Health

Background:

  • Investigated the association between MTHFR gene polymorphisms and severe mental retardation in infants.
  • Focused on the homozygous TT genotype of the MTHFR C677T gene variant.

Purpose of the Study:

  • To determine if infants with the MTHFR gene TT genotype have an increased risk of severe mental retardation.
  • To explore potential ethnic differences in this association.

Main Methods:

  • Case-control study comparing 100 children with severe mental retardation to 743 control infants.
  • DNA analysis from newborn screening filter papers for MTHFR C677T genotypes (TT, CT, CC).

Main Results:

  • No significant overall difference in TT or CT genotypes between cases and controls.
  • Elevated odds ratios (ORs) for TT (1.9) and CT (2.6) genotypes observed in Hispanic children.
  • Results remained consistent after excluding cases with structural birth defects.

Conclusions:

  • Folate metabolism is crucial for understanding birth defect etiologies.
  • Further research into folate, DNA methylation, and mental retardation is warranted.
  • The MTHFR gene may play a role in severe mental retardation, particularly in specific ethnic groups.
Abstract

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