Individual and combined effects of ApoE and MTHFR 677C/T polymorphisms on cognitive performance in Spanish adolescents: the AVENA study.
OBJECTIVE
To examine the individual and combined associations of ApoE and MTHFR 677C/T polymorphisms with cognitive performance in adolescents.


METHODS
The study comprised 412 Spanish adolescents (13 to 18.5 years of age). Cognitive performance (verbal, numeric and reasoning abilities, and an overall score) was measured by the Spanish-version of the SRA-Test of Educational-Ability.


RESULTS
We observed no differences in the cognitive performance study variables in adolescents carrying or not carrying the ApoE epsilon4 variant. Adolescents without the MTHFR 677TT genotype had significantly better cognitive performance than their TT peers. The analysis of the combined effect of these polymorphisms revealed that those individuals carrying both the ApoE epsilon4 variant and the MTHFR 677TT genotype had significantly worse cognitive performance than their peers with other genotype combinations. These findings were independent of sex, age pubertal status, socioeconomic status, physical activity, and skipping breakfast.


CONCLUSIONS
The results of the present study suggest that the ApoE epsilon4 alone is not associated with cognitive performance in adolescents. Individuals with the MTHFR 677TT genotype had slightly impaired cognitive performance, whereas we observed a combined effect of both the ApoE epsilon4 variant and the MTHFR 677TT genotype on cognitive performance. More research is needed in larger population samples to corroborate our findings.
Ruiz
Jonatan R
JR
Unit for Preventive Nutrition, Department of Biosciences and Nutrition at NOVUM, Karolinska Institutet, Huddinge, Sweden. Electronic address: ruizj@ugr.es.
Castillo
Ruth
R
Department of Basic Psychology, School of Psychology, University of Málaga, Spain.
Labayen
Idoia
I
Department of Nutrition and Food Science, University of the Basque Country, Vitoria, Spain.
Moreno
Luis A
LA
Department of Physiotherapy and Nursing, School of Health Sciences, University of Zaragoza, Zaragoza, Spain.
Fuentes
Miguel García
MG
Department of Pediatrics, University of Cantabria, Santander, Spain.
Lamuño
Domingo González
DG
Department of Pediatrics, University of Cantabria, Santander, Spain.
Alvarez Granda
Jesus L
JL
Department of Pediatrics, University of Cantabria, Santander, Spain.
Lucia
Alejandro
A
Universidad Europea de Madrid, Madrid, Spain.
Ortega
Francisco B
FB
Unit for Preventive Nutrition, Department of Biosciences and Nutrition at NOVUM, Karolinska Institutet, Huddinge, Sweden; Department of Medical Physiology, School of Medicine, University of Granada, Spain.
D000293:Adolescent; D053327:Apolipoprotein E4 / Q000235:genetics; D001057:Apolipoproteins E / Q000235:genetics; D003071:Cognition / Q000502:physiology*; D003430:Cross-Sectional Studies; D005260:Female; D056726:Genetic Association Studies; D005838:Genotype; D006710:Homocysteine / Q000502:physiology; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D011110:Polymorphism, Genetic; D012959:Socioeconomic Factors; D013030:Spain; D044465:White People / Q000235:genetics; D055815:Young Adult
D053327:Apolipoprotein E4; D001057:Apolipoproteins E; D006710:Homocysteine; D042965:Methylenetetrahydrofolate Reductase (NADPH2)