Genetic Mapping of Cgdef Gene Controlling Accumulation of 7S Globulin (b-Conglycinin) Subunits in Soybean Seeds

Soy protein consists of mainly 7S globulin (b-conglycinin) and 11S globulin (glycinin). The 7S globulin exerts favorable and unfavorable effects on human nutrition, food process-ing, and human health. Therefore, it is important for the improvement of the soy protein to control the content of 7S globulin. A mutant line lacking the 7S globulin was induced by c-ray irradiation, and the deficiency is controlled by a single recessive gene, cgdef. The Cgdef gene, despite its potential for improvement of the soy protein, has not been assigned to a linkage group of a soybean genetic map. We crossed ‘‘Mo-shi-dou Gong 503’ ’ with plants homozygous or heterozygous for the Cgdef allele and screened an F2 mapping population that segregated with the cgdef allele to locate the Cgdef gene on a soybean genetic map. By linkage analysis, we assigned the Cgdef gene to chromosome 19 a