More than 130,000 Kaiser Permanente members in Northern California are sharing their spit to have their genomes scanned, reports the New York Times. This study aims to "uncover the genetic roots of chronic disease and, perhaps, to find out why some people live longer than others," the Times says, as participants' genetic information will be linked to their medical information (though their names will be removed from the data). In addition, the University of California, San Francisco's Elizabeth Blackburn will be studying a subset of the Kaiser Permanente population. Her lab will be measuring the length of the telomeres present on the chromosomes. "Telomere length is more reflective of things that happen in your life than the genetic hand you are born with," Blackburn says.