Lack of association between the brain-derived neurotrophin factor (C-270T) polymorphism and late-onset Alzheimer's disease (LOAD) in Brazilian patients.
After the identification of the apolipoprotein E gene isoform (APOE-epsilon4) as a risk factor for late-onset Alzheimer's disease (LOAD), the search for other polymorphisms associated with AD has been undertaken by many groups of investigators around the world. These studies have shown controversial results in many populations. More recently, a single nucleotide polymorphism in the promoter region of the brain-derived neurotrophin factor (BDNF) was found to be a risk factor for AD in two independent population studies. Here we report the analysis of this polymorphism in a group of 188 LOAD Brazilian patients compared to matched normal controls. A strong association between the APOE-epsilon4 polymorphism and LOAD was observed, but there was no significant association between this BNDF polymorphism and affected patients. The possibility that other polymorphisms or mutations in this gene play a role in the development of AD cannot be ruled out. However, the results of the present study suggest that in opposition to the two reported studies, this polymorphism does not seem to be implicated in LOAD Brazilian patients. It also shows the importance of replication studies in different populations, as susceptibility loci might differ in different ethnic groups; this will have important implications in future treatments with pharmacological agents.
Human Genome Research Center, Biology Department, Institute of Biosciences, University of São Paulo-IBUSP, São Paulo, Brazil.
Agnes L
AL
Nishimura
João R M
JR
Oliveira
Miguel
M
Mitne-Neto
Camila
C
Guindalini
Ricar
R
Nitrini
Valéria S
VS
Bahia
Paulo R
PR
de Brito-Marques
Paulo A
PA
Otto
Mayana
M
Zatz
D000368:Aged; D000544:Alzheimer Disease / Q000208:ethnology / Q000235:genetics* / Q000378:metabolism*; D053327:Apolipoprotein E4; D001057:Apolipoproteins E / Q000235:genetics; D001921:Brain / Q000378:metabolism / Q000503:physiopathology; D001923:Brain Chemistry / Q000235:genetics*; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D001938:Brazil; D004252:DNA Mutational Analysis; D005260:Female; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005820:Genetic Testing; D006801:Humans; D008297:Male; D008875:Middle Aged; D011110:Polymorphism, Genetic / Q000235:genetics*; D011401:Promoter Regions, Genetic / Q000235:genetics; D015203:Reproducibility of Results; D044465:White People / Q000235:genetics
D053327:Apolipoprotein E4; D001057:Apolipoproteins E; D019208:Brain-Derived Neurotrophic Factor