More Genetic Discoveries Related to Aging

Biosingularity presents a most intriguing story about mice growing old before their time because researchers at Howard Hughes Medical Institute knocked out the gene Sirt6. Sirt6 helps repair DNA nicks. Snowcrash elaborates:
Knocking out a gene that helps repair nicks in DNA causes young mice to develop many of the degenerative characteristics of their wizened elders. Mice lacking the gene develop hunchback, thinning skin, decreasing bone density, and a declining immune system — all in the span of a month.

The researchers do not know whether the accelerated aging-like effects of losing the gene, called 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.

The researchers were put onto the trail of the Sirt genes because of a discovery over twenty years ago that the counterpart gene in yeast, sir2, regulates aging in yeast and preserves genomic stability.

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.

Alt and his colleagues were particularly interested in the sirtuin genes because of the yeast Sir2’s role in maintaining chromatin — the complex of DNA and protein that makes up chromosomes.

“While we’ve been exploring the effects of knocking out each of the sirtuin genes, we’ve found that the SIRT6 knockout produces the most dramatic effects,” he said. In their experiments, Alt and his colleagues explored the effects of knocking out SIRT6 at both the cellular and whole-animal levels.

Biosingularity is an excellent source of information about new biological discoveries, because snowcrash filters out the nonsense reports and concentrates on discoveries of potential importance. Read the entire story at Biosingularity.

Most of you will understand immediately how important this type of research is. Proceeding from discoveries in yeast to discoveries in mice, then to discoveries in larger mammals and humans--that is the inevitable progression as the mysteries of the gene are solved, catalogued, and made ready for use.