SUMMARY
One way to test possible causal relationships between various functional pathways and the aging process is to comparatively analyze polymorphic variation in genes participating in these pathways in elderly populations with different aging-related characteristics. The results of the Human Genome Project now make it feasible to identify most if not all genes involved in the candidate pathways that drive the aging process or confer longevity. For this purpose, efficient genotyping methods are needed that allow the comprehensive sequence analysis of multiple genes at the population level. Using our recently developed two-dimensional gene scanning (TDGS) technology platform, we demonstrated the feasibility of this approach by screening two different populations of centenarians for polymorphic variation in the BRCA1 breast cancer susceptibility gene. The results indicate that using this technology, relatively large numbers of individuals, i.e., hundreds, can be screened in a relatively short time for all possible sequence variants of this very large gene. Although the number of individuals analyzed is still insufficient to draw definite conclusions, a clear trend towards a difference inClamping genomic DNA fragments using the polymerase chain reaction improves the detection of single-base changes. Proc. Natl. Acad. Sci. USA: GULDBERG, P., K.F. HENRIKSEN & F. GUTTLER. Molecular analysis of phenylketonuria in Denmark: % of the mutations detected by denaturing gradient gel electrophoresis. Genomics: MOYRET, C., C. THEILLET, P.L. PUIG, et al. Relative efficiency of denaturing gradient gel electrophoresis and single-strand conformation polymorphism in the detection of mutations in exons 2 to 3 of the p gene. Oncogene: LI, D. & J. VIJG. Multiplex co-amplification of retinoblastoma gene exons after pre-amplification by long-distance PCR. Nucleic Acids Res.: VAN ORSOUW, N.J., R.K. DHANDA, R.D. RINES, et al. Rapid design of denaturing gradient-based two-dimensional electrophoretic gene mutational scanning tests. Nucleic Acids Res.: DHANDA, R.K., W. SMITH, C.B. SCOTT, et al. A simple system for automated two-dimensional electrophoresis: applications to genetic testing. Genet. Testing: VENKITARAMAN, A.R. Breast cancer genes and DNA repair. Science: SHATTUCK-EIDENS, D., A. OLIPHANT, M. MCCLURE, et al. BRCA sequence analysis in women at high risk for susceptibility mutations: risk factor analysis and implications for genetic testing. JAMA: FORD, D., D.F. EASTON & J. PETO. Estimates of the gene frequency of BRCA and its contribution to breast and ovarian cancer incidence. Am. J. Hum. Genet.: PERLS, T.T., K. BOCHEN, M. FREEMAN, et al. Validity of reported age and prevalence of centenarians in a New England sample. Age Ageing: DE BENEDICTIS, G., E. FALCONE, G. ROSE, et al. DNA multiallelic systems reveal gene/longevity associations not detected by diallelic systems: The APOB locus. Human Genet.: DUNNING, A.M., M. CHIANO, N.R. SMITH, et al. Common BRCA variants and susceptibility to breast and ovarian cancer in the general population. Hum. Mol. Genet.: