Copyright © 1999 The American Society of Human Genetics. All rights reserved.
The American Journal of Human Genetics, Volume 65, Issue 4, 1178-1193, 1 October 1999
doi:10.1086/302572
A.I. Yashin1, 2,
,
, G. De Benedictis4, J.W. Vaupel1, 3, Q. Tan1, K.F. Andreev1, I.A. Iachine8, M. Bonafe6, M. DeLuca4, S. Valensin7, L. Carotenuto5 and C. Franceschi6, 7
1 Max Planck Institute for Demographic Research, Rostock, Germany
2 Center for Demographic Studies, Durham, NC
3 Sanford Institute, Duke University, Durham, NC
4 Cell Biology Department, Calabria, Italy
5 System Science Department, University of Calabria, Calabria, Italy
6 Istituto Nazionale Riposo e Cura Anziani, Ancona, Italy
7 Biomedical Science Department, University of Bologna, Bologna, Italy
8 Department of Statistics and Demography, Odense University, Odense, Denmark
Address for correspondence and reprints: Dr. A. I. Yashin, Max Planck Institute for Demographic Research, Doberaner Strasse 114 18057, Rostock, GermanyAbstract
In population studies on aging, the data on genetic markers are often collected for individuals from different age groups. The purpose of such studies is to identify, by comparison of the frequencies of selected genotypes, “longevity” or “frailty” genes in the oldest and in younger groups of individuals. To address questions about more-complicated aspects of genetic influence on longevity, additional information must be used. In this article, we show that the use of demographic information, together with data on genetic markers, allows us to calculate hazard rates, relative risks, and survival functions for respective genes or genotypes. New methods of combining genetic and demographic information are discussed. These methods are tested on simulated data and then are applied to the analysis of data on genetic markers for two haplogroups of human mtDNA. The approaches suggested in this article provide a powerful tool for analyzing the influence of candidate genes on longevity and survival. We also show how factors such as changes in the initial frequencies of candidate genes in subsequent cohorts, or secular trends in cohort mortality, may influence the results of an analysis.
| A Model for Antagonistic Pleiotropic Gene Action for Mortality and Advanced Age The American Journal of Human Genetics, Volume 62, Issue 6, 1 June 1998, Pages 1525-1534 Bruno Toupance, Bernard Godelle, Pierre-Henri Gouyon and François Schächter Abstract Summary:
Association or linkage studies involving control and long-lived populations provide information on genes that influence longevity. However, the relationship between allele-specific differences in survival and the genetic structure of aging cohorts remains unclear. We model a heterogeneous cohort comprising several genotypes differing in age-specific mortality. In its most general form, without any specific assumption regarding the shape of mortality curves, the model permits derivation of a fundamental property underlying abrupt age-related changes in the composition of a cohort. The model is applied to sex-specific survival curves taken from period life tables, and Gompertz-Makeham mortality coefficients are calculated for the French population. Then, adjustments are performed under Gompertz-Makeham mortality functions for three genotypes composing a heterogeneous cohort, under the constraint of fitting the resultant mortality to the real French population mortality obtained from life tables. Multimodal curves and divergence after the 8th decade appear as recurrent features of the frequency trajectories. Finally, a fit to data previously obtained at the angiotensin-converting–enzyme locus is realized, explaining what had seemed to be paradoxical results—namely, that the frequency of a genotype known as a cardiovascular risk factor was increased in centenarians. Our results help explain the well-documented departure from Gompertz-Makeham mortality kinetics at older ages. The implications of our model are discussed in the context of known genetic effects on human longevity and age-related pathologies. Since antagonistic pleiotropy between early and late survival emerges as a general rule, extrapolating the effects measured for a gene in a particular age class to other ages could be misleading. Abstract | | |
| p53 Variants Predisposing to Cancer Are Present in Healthy Centenarians The American Journal of Human Genetics, Volume 64, Issue 1, 1 January 1999, Pages 292-294 Massimiliano Bonafè, Fabiola Olivieri, Daniela Mari, Giovannella Baggio, Rosario Mattace, Paolo Sansoni, Giovanna De Benedictis, Maria De Luca, Stefano Bertolini, Cristiana Barbi, Daniela Monti and Claudio Franceschi | |
| p53 Codon 72 Polymorphism and Longevity: Additional Data on Centenarians from Continental Italy and Sardinia The American Journal of Human Genetics, Volume 65, Issue 6, 1 December 1999, Pages 1782-1785 Massimiliano Bonafè, Fabiola Olivieri, Daniela Mari, Giovannella Baggio, Rosario Mattace, Maurizio Berardelli, Paolo Sansoni, Giovanna De Benedictis, Maria De Luca, Francesca Marchegiani, Luca Cavallone, Maurizio Cardelli, Simona Giovagnetti, Luigi Ferrucci, Loredana Amadio, Rosamaria Lisa, Maria Giovanna Tucci, Leonarda Troiano, Gabriella Pini, Paola Gueresi, Marina Morellini, Sandro Sorbi, Giovanni Passeri, Cristiana Barbi, Silvana Valensin, Daniela Monti, Luca Deiana, Giovanni Mario Pes, Ciriaco Carru and Claudio Franceschi | |