Plasma total homocysteine levels and methylenetetrahydrofolate reductase gene polymorphism in patients with type 2 diabetes mellitus.
BACKGROUND
Thrombotic episodes account for approximately 80% of deaths in type 2 diabetic patients. Hyperhomocysteinaemia is a well recognized independent risk factor for atherosclerosis and thromboembolism. Increased homocysteine levels may occur due to a number of factors including inherited gene polymorphism of methylenetetrahydrofolate reductase (MTHFR) C677T. Here, we evaluate plas- ma total homocysteine (tHcy) levels and frequency of the MTHFR C677T gene polymorphism in asymptomatic healthy volunteers and type 2 diabetic patients with hypertension but without nephropathy. We have also investigated the relationship between tHcy levels and the presence of MTHFR C677T gene polymorphism.


METHODS
Plasma tHcy levels and MTHFR C677T genotype were investigated in a total of 53 subjects. These included asymptomatic healthy volunteers (n = 16), patients with type 2 diabetes (n = 7), subjects with hypertension (n = 12) and patients with both type 2 diabetes and hypertension (n = 18). Renal function, serum lipids and other metabolites were also assessed.


RESULTS
There was no significant difference in tHcy levels between the groups studied. The frequency of MTHFR C677T gene polymorphism observed was similar to that obtained for the general Brazilian population. In patients with type 2 diabetes and hypertension but without impaired renal function, we observed no meaningful correlation between increased tHcy levels and the presence of MTHFR C677T gene polymorphism.


CONCLUSIONS
Type 2 diabetics who are homozygous or heterozygous for the MTHFR C677T gene polymorphism showed normal tHcy levels. Our results further suggest that diabetes without an associated adverse risk profile is not an independent correlate of increased tHcy levels.
Soares
Anna L
AL
Faculty of Pharmacy, Federal University of Minas Gerais, Belo Horizonte, Brazil.
Fernandes
Ana P
AP
Cardoso
Jarbas E
JE
Sousa
Marinez O
MO
Lasmar
Marcelo C
MC
Novelli
Bethânia A
BA
Lages
Geralda F
GF
Dusse
Luci M
LM
Vieira
Lauro M
LM
Lwaleed
Bashir A
BA
Carvalho
Maria G
MG
D000328:Adult; D001938:Brazil; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000097:blood*; D005260:Female; D005838:Genotype; D006710:Homocysteine / Q000097:blood*; D006801:Humans; D020138:Hyperhomocysteinemia / Q000235:genetics*; D006973:Hypertension; D008297:Male; D042965:Methylenetetrahydrofolate Reductase (NADPH2) / Q000235:genetics*; D008875:Middle Aged; D020641:Polymorphism, Single Nucleotide
D006710:Homocysteine; D042965:Methylenetetrahydrofolate Reductase (NADPH2)