Newly-discovered class of genes determines ?and restricts ?stem cell fate
Research on adult stem cells found in the skin hints at a new class of genes, according to a study from investigators at the University of Pennsylvania School of Medicine. These genes ?dubbed pangenes ?can both govern a stem cell's fate and put a hold on future differentiation until the time is right. Understanding the molecular control of these genes has implications for therapies that involve t...International Team Determines Geographic Origin of Leprosy
Leprosy likely originated in East Africa and spread to Asia and Europe before being imported into West Africa by explorers, report scientists in this week's issue of Science. The findings enrich the historical understanding of leprosy's global migration and contradict a commonly held view that leprosy spread to West Africa directly from East Africa, say the researchers. The international t...Researchers Discover Gene That Determines Asthma Susceptibility By Regulating Inflammation
Disruption of a single gene, Nrf2, plays a critical role in determining the susceptibility to asthma. A research team led by Shyam Biswal, PhD, at the Johns Hopkins Bloomberg School of Public Health found the absence of Nrf2 exacerbated allergen-mediated asthma in mice models. The study’s findings, published in the July 4, 2005, edition of the Journal of Experimental Medicine, may hold therapeuti...Weapon performance determines mating success in the collared lizard
In territorial species with polygynous mating systems, reproductive success reflects phenotypic variation. At the gross level, such phenotypic variation can include that of body size and weapon morphology, as well as of weapon function and performance. In a study published in the September issue of The American Naturalist, A. Kristopher Lappin (Northern Arizona University) and Jerry F. Hus...Genetic tug of war determines sexual differentiation
Whether or not a fertilized mammalian egg ultimately develops into a male or female is determined by the winner of a tug of war between two different genes encoding signaling proteins and the divergent pathways they control, according to a new study led by Duke University Medical Center cell biologists. In their experiments in mice, the researchers found that two specific genes, Wnt4 and F...Researchers discover mechanism that determines when detailed memories are retained
The levels of a chemical released by the brain determine how detailed a memory will later be, according to researchers at UC Irvine. The neurotransmitter acetylcholine, a brain chemical already established as being crucial for learning and memory, appears to be the key to adding details to a memory. In a study with rats, Norman Weinberger, research professor of neurobiology and behavior, a...