J Korean Child Neurol Soc.  1998 Oct;6(1):55-61.

The Prevalence of 677C=>T Mutation in Methylenetetrahydrofolate Reductase (MTHFR) Gene in Spinal Neural Tube Defect

• Lee BH
• Wang KC
• Cheong HI

Abstract

PURPOSE: There is evidence that folic acid given before and during the first 4 weeks of pregnancy can prevent more than 50% of neural tube defect. It suggested that folic acid play a great role when a neural tube closes. Methylenetetrahydrofolate reductase (MTHFR) is an important enzyme in folate metabolism. Since the gene locus and mutation of MTHFR were identified, increased frequency of MTHFR variant was reported in neural tube defect. We studied the frequency of the 677C=>T mutation in the MTHFR gene to determine whether this MTHFR gene variant is more common in persons with neural tube defect and their families compared to a control population.
METHODS
The study group consisted of 21 patients with meningomyelocele, 40 their parents and 7 siblings who were managed in Seoul National University College of Medicine and Dankook University Hospital during the period from Jan. 1997 to Dec. 1997. The control group consisted of 25 parents aged between 25 to 50 years who had given birth to, at least, one normal infant and 18 children under 16 years without neural tube defect. DNA was extracted from peripheral blood and a segment of the MTHFR gene was amplified using PCR technique. And treated with restriction enzyme, Hinf1. The restriction pattern was analyzed.
RESULTS
The frequency of the three genotypes were as follows: normal (-/-), 47.0%; heterozygote (+/-), 41.2%; and homozygote (+/+), 11.8% in neural tube defect group and (-/-), 25.6%; (+/-), 58.1%; (+/+), 16.3% in control group. The MTHFR gene variant was present 9.5% of those with meningomyelocele, 13.3% of their mothers 10% of their fathers, and 10.3% of siblings.
CONCLUSION
1)There is no increase of the frequency of MTHFR variant polymorphism in neural tube defect compared to control group. These observations indicate that while there maybe racial differences in the mutation frequency, expanded studies involving larger numbers of subjects are required. 2) To elucidate the role of various genetic factors influencing on homocysteine levels and vitamin nutrition, research on other genetic variants, such as folic acid and vitamin B12-related enzymes and receptors, are recommended,

Keyword

Methylenehydrofolate reductase; Neural tube defect; 677C -> T mutation

MeSH Terms

Child
DNA
Fathers
Folic Acid
Genotype
Heterozygote
Homocysteine
Homozygote
Humans
Infant
Meningomyelocele
Metabolism
Methylenetetrahydrofolate Reductase (NADPH2)*
Mothers
Mutation Rate
Neural Tube Defects*
Neural Tube*
Parents
Parturition
Polymerase Chain Reaction
Pregnancy
Prevalence*
Seoul
Siblings
Vitamins
DNA
Folic Acid
Homocysteine
Methylenetetrahydrofolate Reductase (NADPH2)
Vitamins