[Total plasma homocysteine levels. Relationship with plasmatic folic acid levels and 677C T polymorphism of 5,10-methylenetetrahydrofolate reductase].
BACKGROUND
Moderately increased plasma homocysteine (Hcy) in children has been associated with stroke and venous thrombosis and with a parental history of cardiovascular disease (CVD). Evaluation of Hcy concentrations during childhood and study of the factors determining its concentrations could play an important role in the primary prevention of CVD. Objective To detect cases of hyperhomocystinemia and to examine the association between Hcy levels and plasma folic acid levels and 677C T polymorphism of 5,10-methylenetetrahydrofolate reductase (MTHFR).


METHODS
The relationship between plasma Hcy levels, plasma folic acid levels, and the three genotypes of 677C T MTHFR polymorphism was investigated in 127 children (aged 2-18 years) and in 105 parents by multiple linear regression.


RESULTS
The median Hcy levels were 5.00 mol/l in the children and 8.00 mol/l in the parents. Plasma folic acid levels were normal in all of the patients. The prevalence of the three genotypes in the children was 32.3 % for the CC genotype, 42.5 % for the CT genotype and 15.7 % for the TT genotype. Hcy concentrations were significantly higher in children with the TT genotype (p 0.018). Multiple linear regression revealed a positive direct effect of age (b 0.029, p 0.002) and a negative effect of genotype TT (b 3.886, p 0.002) on Hcy concentration. Hcy concentration was inversely correlated with folic acid levels but this correlation did not reach statistical significance.


CONCLUSIONS
No cases of hyperhomocystinemia were found. To evaluate Hcy, age and plasma folic acid levels have to be taken into account in case there is a 677C T mutation. Hcy concentrations should be determined in older children with a family history of atherothrombosis and other risk factors for premature CVD.
Dalmau Serra
J
J
Unidad de Nutrición y Metabolopatías, Hospital Infantil La Fe, Valencia, Spain. jdalmaus@ono.com
Ferrer Lorente
B
B
Modesto Alapont
V
V
Guillén Domínguez
M
M
Vázquez Gomis
R
R
Corella Piquer
D
D
Cabello Tomás
M L
ML
García Gómez
A M
AM
D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003596:Cytosine; D005260:Female; D005492:Folic Acid / Q000097:blood*; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D008297:Male; D008754:Methylenetetrahydrofolate Dehydrogenase (NADP) / Q000235:genetics*; D011110:Polymorphism, Genetic; D012044:Regression Analysis; D014443:Tyrosine
D006710:Homocysteine; D014443:Tyrosine; D003596:Cytosine; D005492:Folic Acid; D008754:Methylenetetrahydrofolate Dehydrogenase (NADP)