BIO207H5 Lecture Notes - Lecture 14: Reginald Punnett, William Bateson, Genetic Linkage
Document Summary
The discovery of genetic linkage: william bateson and reginald punnett, in a series of crosses with sweet peas, found evidence of genetic linkage. They crossed pure-breeding purple-flowered, long-pollen plants to white-flowered, round- pollen plants; the purple, long-pollen f1 were interbred to produce f2. In the f2 progeny, the number of purple-flowered, long-pollen plants and the red-flowered, round-pollen plants were seen in larger proportion than expected. These were the same phenotypes as the original parents. The nonparental types were observed less frequently than expected. What bateson and punnett concluded: bateson and punnett suggested that an unknown mechanism kept the two parental gamete combinations together, which they called (cid:862)coupling(cid:863) They described the appearance of the nonparental types as (cid:862)repulsion(cid:863) of the parental alleles. Morgan"s crosses: morgan studied the white (eye color) and miniature (wing size) genes, he crossed females pure-breeding for white eyes and small wings (wm/wm) to males that were wild type for both (w m /y)
