9. Linkage of Dt with loci in chromosome 9. Data published in 1938 suggested that Dt was linked with C. To test this indication the following data were obtained:

Genes Linkage Phase XY Xy xY xy Total % Recomb.
Dt Ws C S 1663 525 690 119 2996 41
Dt Wx C B 682 65 472 677 2206 40.9
Dt Sh C S 679 100 156 138 1073 27

These data definitely prove that Dt is in chromosome 9 and further indicate that Dt should lie close to yg2. Tests with yg2 have been handicapped by the fact that all available yg2 stocks are homozygous for recessive c and it has been necessary to extract a yg2 C stock.