Tom Johnson
Institute for Behavioral Genetics
University of Colorado at Boulder
Tom Johnson recalls seeing Our Friend the Atom, a Disney TV movie, when he was 7 or 8 years old. It was produced as part of a public relations effort called “Atoms for Peace,” in which positive propaganda was developed to promote the use of atomic energy. What stuck in Tom's mind was the nuclear genie that was let out of the bottle and couldn't be put back in. Tom related this to moving forward with science and was hooked.
Today Tom is looking for the right genes, the ones that could make us live longer. His goal is to identify longevity genes in mammals. Interestingly, no mammalian genes have ever been identified that weren't first identified in other species. By working with a large population of genetically diverse mice, they plan to identify variants and isolate the genes that contribute to a longer life.
Knowing the gene makeup of the mice will allow them to “build” a mouse with a greater lifespan. These genetically altered mice will live with environmental conditions and dietary restrictions that have already proven conducive to longer life.
Tom has seen a remarkable change in the level of interest and research related to aging. When he began his work in the 1980s it was not a popular topic, even among biologists. This year at the C. elegans meeting at UCLA half of the presenters were addressing issues related to aging. Tom remains excited about “getting past the acceptance of the inevitability of aging and discovering that longevity can be manipulated…health can be modulated.”
Michal Masternak
School of Medicine
Southern Illinois University
Michal Masternak is not suggesting that we need to be smaller to live longer. But he is interested in discovering why dwarf mice live longer.
Michal's work expands on the work of Andrzej Bartke (see article below) that produced an Mprize winning mouse. The long life of Andrzej's mouse was a result from “knocking out” the growth hormone receptor. Building on that success and recognizing the fact that several types of dwarf mice have a longer lifespan than other mice is a focus of Michal's team of researchers. They will breed mice lacking both growth hormone and growth hormone receptor.
The other interesting focus of Michal's observations relates to insulin sensitivity. Insulin is a hormone that is released by the pancreas in response to a rise in the level of glucose in the blood. Insulin prevents a further increase in the blood glucose level and causes it to fall gradually. A healthy body maintains appropriate levels of insulin and glucose. A lack of insulin and/or trouble responding to insulin is responsible for the high blood glucose levels that characterize diabetes. Diabetics are often overweight and overweight people tend to be insulin resistant. Additionally, people become insulin resistant and glucose intolerant as they age.
The team will carry out their research by breeding 80 extremely small and therefore expected to be exceptionally long-lived but otherwise normal mice to determine the longevity. Additionally other groups will be used to study insulin/glucose function to be able to correlate these changes with longevity outcome. This is in Michal's words, “Discovering as we go with the hope of creating a model to start the search for the genes that indicate a long, healthy life. We expect to be able to isolate the genes and make alterations without changing the whole phenotype.” In other words, Michal does not see the need to make people smaller but he would like them to live longer in good health.
Follow Tom and Michal's progress on our site and look for more new competitors to be added in the coming weeks.
