¹Departamento de Biologia, ICB, UPE.

² Núcleo de Neurologia do Comportamento, FCM, UPE.

Alzheimer disease (AD) is a neurodegenerative disorder, characterized for the loss of intellectual potentiality in high degree, change of personality, aphasia, apraxia and agnosia. Folate and B12 vitamin are important in a great number of metabolic reactions in the central nervous system and some studies have associated its low serum levels to the increase of AD development risk. Folate transport is determined by reduced-folate carrier - RFC and different genotypes for A80G locus of the RFC-1 have been associated to the variation of folate concentration. The aim of this work was to investigate the role of G80A polymorphism of RFC-1 gene on AD development jointly to MTHFR gene polymorphism and to estimate the risk rate conferred for G80A mutation. There were 30 patients with probable and possible AD of both gender, equal or superior to 60 years old taken care of in the Núcleo de Neurologia do Comportamento, FCM, UPE. The control group consisted of 30 individuals in the same average age, without clinical evidences of dementia. The genomic DNA was extracted by commercial kits, from leukocytes. The genotypes were carried out through PCR (Polymerase Chain Reaction) and RFLP (Restricton Fragment Length Polymorphism) methods. The amplified PCR fragments presented 230pb for G80A polymorphism in RFC-1 gene and 198pb for C677T polymorphism in MTHFR gene. A-G transition creates a small restriction site for HhaI and C-T transition creates a small restriction site for HinfI. The digested products of amplification had been separated by eletrophoresis in 3% agarose gel for RFC-1 G80A polymorphism and in 2% agarose gel for MTHFR C677T polymorphism. Both were observed in ultraviolet. The population was in Hardy–Weinberg equilibrium. It was not observed significant difference in gene frequencies between patients and controls for G80A polymorphism (p=0.60) or G80A associated to C677T polymorphism (0.5367).The Odds ratio for G80A RCF1 polymorphism revealed some risk although it was not significant yet. The results do not suggest a relationship between the risk of AD and the presence of G80A mutation of RFC yet.