Sci. Aging Knowl. Environ., 3 October 2001
Aiming for Ames: Test promises to ease breeding task
Key Words: Ames Prop-1 genotyping dwarf mice
Abstract: Ames dwarf mice might be small, but they promise to wield great power--at least in the field of aging. These animals live 49% to 64% longer than their normal littermates; studying them is already hinting at physiological mechanisms that underlie longevity. A newly published method to rapidly identify the Ames defect at the DNA level should facilitate the ability to breed this strain and to distinguish affected individuals from their siblings even before they start to exhibit the hallmark characteristics: Ames dwarf mice carry two defective copies of the Prop-1 gene, which causes defects in the growth hormone signaling pathway and consequent dwarfism. In addition, the animals are sterile or near-sterile; hormone treatments partially counteract this condition, but it's not easy to produce offspring from two subfertile Ames dwarf mice. Although the Prop-1 gene was isolated in 1996, no one had published a method by which to detect the DNA lesion in animals until now. Doll� and colleagues have developed a standard polymerase chain reaction-based test that allows investigators to distinguish animals that carry zero, one, or two copies of defective Prop-1 by detecting diagnostic bands of DNA on a gel. This ability will allow researchers to identify animals suitable for breeding: ones that look normal yet harbor a single copy of the defective gene. In addition, the technique offers a way to distinguish Ames dwarf mice even when they are very young, before the growth differences become apparent. That capability could facilitate studies of these animals at the beginning--as well as the end--of their very long lives.
--Evelyn Strauss; suggested by James M. Harper
Citation: E. Strauss, Aiming for Ames: Test promises to ease breeding task. Science's SAGE KE (3 October 2001), http://sageke.sciencemag.org/cgi/content/abstract/sageke;2001/1/nw4
Science of Aging Knowledge Environment. ISSN 1539-6150