Scientists are discovering all sorts of interesting things now that mainstream calorie restriction research is focused on sirtuins: "The research on SIRT6 is part of a broad effort in the Alt laboratory to study the role of a family of seven known mammalian sirtuin genes. These studies were prompted by findings some two decades ago that a yeast counterpart called Sir2 maintains genomic stability and regulates aging in yeast cells. Researchers had also found that enhancing the activity of Sir2's counterparts in the roundworm and fruit fly extended their life span. ... we've found that the SIRT6 knockout produces the most dramatic effects ... The researchers do not know whether the accelerated aging-like effects of losing [SIRT6] relate to its role in DNA repair. Nor do they know whether the degenerative effects are relevant to the natural aging process. However, they said, the discovery offers an intriguing new model for studying DNA repair, as well as its possible role in aging-related degeneration."