Scientists around the globe may soon be studying tiny bits of George Church. The Harvard Medical School professor of genetics will be one of the first people to have stem-cell lines created from his skin cells propagated and distributed worldwide--along with a record of the cells' donor's identity and genetic and medical quirks.

Church and his collaborators hope that the cells will add a new dimension to genetic studies of human disease. Most studies compare genomes of a group of people with a particular phenotype--say, diabetes or heart disease--with healthy volunteers. But adding stem-cell lines, which can be differentiated into the myriad tissue types affected by disease, should allow scientists to search for molecular changes that are the intermediary between genes and the manifestation of a disease. "For nearly every genetic trait variation, there is a change at the cellular level," says Church.

This new addition to genomics studies comes thanks to induced pluripotent cell reprogramming, a recent breakthrough in stem-cell research that allows scientists to create immortal cell lines from healthy human donors that, like embryonic stem cells, can both replicate themselves and differentiate into many types of tissue. While cultured cells are a ubiquitous part of biomedical research, used to test drugs, study disease, and engineer tissue, most cells cannot form different tissue types, and they come from anonymous donors--meaning that medical and other characteristics of the donor are unknown. In addition, many "immortal" cell lines, which can divide indefinitely, are derived from tumor cells and thus have abnormal chromosomes.

Church won't be alone in distributing his cells. The scientist aims to create hundreds or thousands of cell lines over the next few years as part of the Personal Genome Project, an effort that he launched two years ago to capitalize on advances in gene-sequencing technologies. So far, the project has enrolled 10 volunteers--and garnered headlines, mainly for its genomic-era exhibitionism. Volunteers, including Harvard psychologist Steven Pinker and entrepreneur Ester Dyson, released their medical records and preliminary genetic analyses on the Web earlier this month. But media attention has mostly ignored that fact that they've also given something that may be even more personal. Each has undergone a skin biopsy, which will be used to generate stem-cell lines.

The lines will allow scientists to study cells with a known genetic and clinical profile. Those working with cells derived from Steven Pinker, for example, would know that he suffers from basal cell carcinoma, lichen planus (an inflammatory skin condition), and Reynaud's syndrome (a hypersensitivity of the fingers and toes to extreme temperatures).