The rare accelerated aging (or progeroid) conditions have a lot to teach us about "normal" aging, as illustrated by this EurekAlert! piece: "Patients with Werner Syndrome manifest signs of aging, such as skin wrinkling, baldness, or hair graying, in their teens. Most die in their 40's or 50's due to a predisposition to diseases like cancer. ... Cancer is almost always related to chromosomal instability. If telomeres are lost on individual chromosomes, then chromosomes are not protected and can fuse with other nonprotected chromosomes. Then when cells divide, chromosomes randomly break, leading to genome instability ... The lack of a single protein (WRN) [mutant or nonfunctional in Werner Syndrome] induced loss of some telomeres, leading to a premature cellular growth arrest ... When we put telomerase into cells [it] fixed the defect by elongating short telomeres seen in Werner Syndrome cells ... We study this disease because it is an excellent model for aging, and we show here a direct relation between aging, telomere loss, and cancer occurrence. I predict that cancer in older people has precisely the same basis as that seen in Werner Syndrome patients. That is why this was such a satisfying study."