title: -308(G/A) TNF-alpha gene polymorphism and risk of depression late in the life.
abstract: The relationship between major depression (MD) and dementia in the elderly is still not clear, but it is certain that the immune system and in particular, pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-alpha, play a key role in the mechanisms underlying the two neuro-psychiatric disorders. In our experience, the -308(G/A) single nucleotide polymorphism (SNP) in the TNF-alpha gene is associated with earlier age at onset in patients affected by Alzheimer's disease (AD). The aim of this study was to investigate the association between the -308(G/A) SNP and late-life MD in elderly people without dementia. Blood samples were obtained from 50 subjects, after screening with the geriatric depression scale (GDS>or=15) and mini-mental state examination (MMSE>or=24). The -308 (G/A) SNP was genotyped by SSP-PCR amplification. Two-hundred-fourty age-matched healthy volunteers were taken as the control group. We identified different genotype and allele distributions of the SNP in old depressed patients and healthy controls (HC). Our results evidenced a significantly higher percentage of the GG genotype in depressed subjects (84.0% vs. 68.3%; p=0.007) and consequently of the G allele (92.0% vs. 81.9%; p=0.05). The presence of the GG genotype raised the risk of developing MD (odds ratio=OR=2.433, confidence interval=Cl=1.09-5.43). Our findings suggested that the investigated TNF-alpha SNP may: (1) affect MD susceptibility; (2) be involved both in AD and MD development, but probably with a distinct role in the two pathologies.
authors.affiliation: Department of Clinical Medicine and Prevention, University of Milano Bicocca, SCC Geriatrics, Monza, Italy.
authors.forename: A P
authors.initials: AP
authors.lastname: Cerri
authors.forename: B
authors.initials: B
authors.lastname: Arosio
authors.forename: C
authors.initials: C
authors.lastname: Viazzoli
authors.forename: R
authors.initials: R
authors.lastname: Confalonieri
authors.forename: F
authors.initials: F
authors.lastname: Teruzzi
authors.forename: G
authors.initials: G
authors.lastname: Annoni
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004247:DNA / Q000235:genetics*; D003863:Depression / Q000235:genetics*; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D008297:Male; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D011379:Prognosis; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*
chemical_list: D014409:Tumor Necrosis Factor-alpha; D004247:DNA