[The special genetics of the chicken]

Studies on inheritance of a number of traits, peculiarities of the karyotype, and chromosome mapping in chicken are reviewed. Prominent among these are studies on behavioral genetics, which are performed at different levels and in different aspects: neuromuscular apparatus and entire organism, behavior and population structure, and behavior and individual fecundity. Creation of lines that differed in neural reactivity provided a model for study of systemic control of cytogenetic processes. On the basis of data on genetic control of feather color, a hypothesis was proposed concerning the mechanism of action of the eumelanin suppressor gene. In the Department of Genetics and Breeding of St. Petersburg State University, research was reformed on the relationships between hereditary and non-hereditary variability, as well as the determination and realization of the genotype reaction norm. In the framework of this research, a study on the variability of chicken growth was performed. A single short-term cooling of chickens during the first week of life resulted in a prolonged (up to eight-week) alteration of growth rate. The following structural genes were mapped in chicken mitotic chromosomes by the method of in situ hybridization: the gene for the transferrin receptor, the beta-globin gene cluster, the homologues of the human ZFY and SRY gene families, the viral oncogene v-fos, and a TG-rich minisatellite.