Methylenetetrahydrofolate reductase polymorphism is not risk factor for Down syndrome in North India.
BACKGROUND
Down syndrome (DS) is the most common cause of mental retardation of genetic etiology with the prevalence rate of 1/700 to 1/1000 live births worldwide. Several polymorphisms in folate/homocysteine metabolism pathways genes have been reported as a risk factor in women for bearing DS child, but very few studies investigated these polymorphisms in DS cases whether there are a risk factor for being DS or not.


OBJECTIVE
We have investigated the association of methylenetetrahydrofolate reductase (MTHFR) with the occurrence of DS in Indian population. MTHFR is one of the key regulatory enzymes involved in the metabolic pathway of homocysteine responsible for the reduction of methyltetrahydrofolate. A total of 32 DS cases and 64 age, sex matched controls were genotyped for MTHFR C677T polymorphism by polymerase chain reaction-restriction fragment length polymorphism.


RESULTS
The observed genotype frequencies were CC = 0.81; CT = 0.17 and TT = 0.02 in controls and CC = 0.81 and CT = 0.19 in DS cases. Frequency of T allele in DS and controls were 0.09 and 0.1, respectively. Significant difference in the distribution of mutant 677T allele was not observed between DS cases and controls (odds ratio = 0.915; 95% confidence intervals: 0.331-2.53; P = 0.864).


CONCLUSIONS
Results of this study indicate that MTHFR C677T polymorphism is not risk factor for DS.
Department of Biotechnology, Human Molecular Genetics Laboratory, VBS Purvanchal University, Jaunpur, Uttar Pradesh, India.
Vandana
V
Rai
Department of Biotechnology, Human Molecular Genetics Laboratory, VBS Purvanchal University, Jaunpur, Uttar Pradesh, India.
Upendra
U
Yadav
Department of Biotechnology, Human Molecular Genetics Laboratory, VBS Purvanchal University, Jaunpur, Uttar Pradesh, India.
Pradeep
P
Kumar
Department of Biotechnology, Human Molecular Genetics Laboratory, VBS Purvanchal University, Jaunpur, Uttar Pradesh, India.
Sushil Kumar
SK
Yadav
Down syndrome; homocysteine; methylation; methylenetetrahydrofolate reductase; polymorphism