BACKGROUND: There are high expectations regarding the potential for the communication of DNA-based disease risk estimates to motivate behaviour change. OBJECTIVES: To assess the effects of communicating DNA-based disease risk estimates on risk-reducing behaviours and motivation to undertake such behaviours.
Studies were conducted to directly test whether the introduction of telomerase protects cancer-prone human mammary epithelial cells from chromosomal instability and spontaneous immortalization. Using a model for Li Fraumeni Syndrome (LFS), infection of human telomerase resulted in maintenance of telomere lengths, extension of in vitro lifespan, and prevention of spontaneous immortalization.
Once thought to be an extremely complex conundrum of weak genetic and environmental effects, exceptional longevity is beginning to yield genetic findings. Numerous lower organism and mammalian models demonstrate genetic mutations that increase life-span markedly. These variations, some of them evolutionarily conserved, inform us about biochemical pathways that significantly impact upon longevity. Centenarian studies have also proven useful as they are a cohort that, relative to younger age groups, lacks genotypes linked to age-related lethal diseases and premature mortality.
Centenarians are people who escaped from major common diseases, including cancer, and reached the extreme limits of human life-span. The analysis of demographic data indicates that cancer incidence and mortality show a levelling off around the age of 85-90 years, and suggests that oldest old people and centenarians are protected from cancer onset and progression.
Centenarians exist at the extreme of life expectancy and are rare. A number of pedigree and molecular genetic studies indicate that a significant component of exceptional longevity is genetically influenced. Furthermore, the recent discovery of a genetic locus on chromosome 4 indicates the powerful potential of studying centenarians for genetic factors that significantly modulate aging and susceptibility to age-related diseases. These studies include siblings and children of centenarians.
OBJECTIVE: To test whether cholesterol ester transfer protein (CETP) genotype (VV homozygosity for I405V) is associated with preservation of cognitive function in addition to its association with exceptional longevity. METHODS: We studied Ashkenazi Jews with exceptional longevity (n = 158; age 99.2 +/- 0.3 years) for the associations of CETP VV genotype and lipoprotein phenotype, using the Mini-Mental State Examination (MMSE). To confirm the role of CETP in a younger cohort, we studied subjects from the Einstein Aging Study (EAS) for associations between CETP VV and cognitive impairment.
A cholesteryl ester transfer protein (CETP) genotype (V/V homozygosity for I405V, NCBI dbSNP rs5882) has been associated with preservation of cognitive function in old age, in addition to its associations with exceptional longevity and cardiovascular disease. We tested the hypotheses that this polymorphism was associated with either level of cognitive function or lifetime cognitive change in 525 participants who took part in the Scottish Mental Survey of 1932. Participants took the same well-validated mental ability test at ages 11 and 79.
The Journal of Clinical Endocrinology and Metabolism
CONTEXT: Exceptional longevity is associated with raised serum TSH. OBJECTIVE: The aim of this study was to examine whether offspring of people with exceptional longevity have elevated serum TSH and whether specific single nucleotide polymorphisms (SNPs) in the TSH-B gene and TSH receptor (TSHR) gene are associated with this phenotype. DESIGN/SETTING/PATIENTS: We measured serum TSH and free T(4) in Ashkenazi Jewish centenarians (n = 232; median age, 97 yr), their offspring (n = 366; median age, 69 yr), and age-matched controls without familial longevity (n = 163; median age, 70 yr).
JAMA: the journal of the American Medical Association
CONTEXT: Polymorphisms in the cholesteryl ester transfer protein (CETP) gene have been associated with exceptional longevity and lower cardiovascular risk, but associations with memory decline and dementia risk are unclear. OBJECTIVE: To test the hypothesis that a single-nucleotide polymorphism (SNP) at CETP codon 405 (isoleucine to valine V405; SNP rs5882) is associated with a lower rate of memory decline and lower risk of incident dementia, including Alzheimer disease (AD).
Our study purpose was to compare a disease-related polygenic profile that combined a total of 62 genetic variants among (i) people reaching exceptional longevity, i.e., centenarians (n = 54, 100-108 years, 48 women) and (ii) ethnically matched healthy controls (n = 87, 19-43 years, 47 women).