9632338 Antonovics The laws of genetics predict that the genes contributed by each parent to their progeny will again reappear in a 50:50 ratio in the gametes of the progeny. However, increasingly it has been found that some genes are "selfish" and alter the pattern of transmission so as to favor their representation in future generations. This study will investigate a possible example of such biased transmission involving the gene determining the mating type of a fungus that infects and sterilizes the flowers of a common plant species. Since fusion of cells of opposite mating types is necessary for the fungus to cause disease, the bias should be disadvantageous, but instead it has spread in natural populations. The cause of the bias and possible reasons for its spread will be investigated. The study is important in understanding disease spread in natural and agricultural plant populations, and in understanding unusual mechanisms in genetic transmission. These mechanisms may prove useful for engineering the rapid spread of particular genes that either limit pathogen growth, or enhance the spread of pathogens used in the biological control of weeds.
