RESUMEN
Human longevity has been associated with mitochondrial DNA (mtDNA) coding region polymorphisms, as well as the C150T polymorphism in the non-coding region in previous studies especially in Europeans. This study investigated the potential association between the mtDNA C150T polymorphism and longevity in a Han Chinese population. Leukocyte mtDNAs from two groups of a Han Chinese population living in Dujiangyan city of Sichuan province, including 556 longevous individuals (90-108 years-old) and 403 unrelated controls, were analyzed and mtDNA haplogroups were determined by sequencing control regions and restriction fragment length polymorphisms (RFLPs) in coding regions. Our results did not show a universal association between the mitochondrial C150T polymorphism and longevity in this population. Even when mtDNA haplogroups defined by C150T and gender were taken into account, there was no significant association with longevity. In conclusion, the mtDNA C150T polymorphism could not present an accumulation in an elderly Han Chinese population. Previous association studies might have been influenced by nuclear DNA and/or environment factors.
Asunto(s)
Pueblo Asiatico/genética , ADN Mitocondrial/genética , Longevidad/genética , Polimorfismo Genético/genética , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , China , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Longitud del Fragmento de RestricciónRESUMEN
BACKGROUND: Previous studies have suggested a probable association between the polymorphism of a microsatellite locus located in the promoter of IGF1 (Insulin-like growth factor 1) gene and the serum level of IGF1, as well as many age-related diseases. Based on these results, we hypothesized that this polymorphism may influence longevity in humans. We performed an association study in a Han Chinese population to test this hypothesis. FINDINGS: We recruited 493 elderly Han Chinese individuals (females >/= 94; males >/= 90) and 425 young individuals (controls) from Dujiangyan (Sichuan province, China). The genotype distributions and allele frequencies of the microsatellite site in the elderly and control groups were compared by chi square test.Our results suggested that there was no association between the microsatellite polymorphism and longevity in our Han Chinese population. However, there were more male persons with 18/21 genotype in elderly group than that in control group (11.11 vs. 5.45%, p = 0.011). As the difference was not significant when corrected by Bonferroni method, we speculate that the 18/21 genotype can not be functional in longevity; however, it may link with the real functional loci as there is a long haplotype block embracing the microsatellite locus. CONCLUSIONS: There was no association between polymorphism of the microsatellite in promoter of IGF1 gene and longevity in our study. Future association studies containing the long haplotype block are deserved and can test our speculation of the potential linkage of 18/21 genotype and functional loci.
Asunto(s)
Anciano de 80 o más Años , Brotes de Enfermedades/estadística & datos numéricos , Estilo de Vida , Longevidad , Población Rural/estadística & datos numéricos , Anciano , Índice de Masa Corporal , China , Estudios Transversales , Conducta Alimentaria , Femenino , Conductas Relacionadas con la Salud , Humanos , Masculino , Tamizaje Masivo , Factores SexualesRESUMEN
INTRODUCTION: The insertion/deletion polymorphism of the angiotensin-converting enzyme (ACE) gene has been reported to associate with human longevity. However, little information is available in a Han Chinese longevity population.Therefore, we investigated the association of the ACE gene insertion/ deletion polymorphism with longevity in a Han Chinese population. MATERIALS AND METHODS: We compared the distribution of ACE insertion/deletion genotype and allele frequencies in two groups: a longevity group (399 subjects) aged over 90 years and a control group (302 subjects) aged less than 60 years. RESULTS: No difference in genotype and allele frequencies of the ACE gene insertion/deletion polymorphism was observed between the longevity group and the control group.When adjusting for gender, the difference between the longevity group and the control group was also not significant regarding the frequencies of the genotypes (male, p=0.994 and female, p=0.797) as well as allele frequencies (male, p=0.969 and female, p=0.884). CONCLUSIONS: No association of the ACE gene insertion/deletion polymorphism with longevity was observed in our Han Chinese population.
Asunto(s)
Eliminación de Gen , Longevidad/genética , Mutagénesis Insercional , Peptidil-Dipeptidasa A/genética , Anciano de 80 o más Años , Pueblo Asiatico/genética , China , Femenino , Frecuencia de los Genes , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo GenéticoRESUMEN
Previous studies have indicated that genetic variations in the factors of insulin/insulin-like growth factor 1 (IGF-1) signaling pathway could influence human life-span by affecting IGF-1 levels. The promoter region of the IGF-1 gene is an obvious candidate and has not been studied clearly. To explore the potential role of the promoter region variation of IGF-1 gene in longevity, we investigated 485 longevity subjects and 392 younger individuals from Dujiangyan, China. By sequencing about 2.5 kb (kilo base pairs) upstream the transcription start site of exon 1 of the IGF-1 gene in 30 individuals from both groups respectively, we acquired three previously described SNPs (-439T/A (rs2288377), -541T/C (rs5742612) and -1246C/T (rs35767)). We examined the association between these three SNPs and longevity by comparing the distribution of genotypes, alleles, and haplotypes in both the longevity and control groups. None of these variants were found to be associated with longevity. Our results suggest that there is no association between SNPs in the promoter region of IGF-1 gene and longevity in the Han Chinese population.
