The following three recessive genes are found in corn. Brittle endosperm (bt1), glossy leaf (gl17), and ragged seedling (rgd1). A tri-hybrid is test-crossed producing the following offspring.
brittle, glossy, ragged 258
brittle, glossy 121
ragged 119
glossy, ragged 26
wild-type 242
brittle, ragged 7
glossy 5
brittle 22
800
a--if the genes are linked, determine the relative order and map distances (both measured and actual).
b--what is the coefficient of coincidence for double crossovers.
c--Is there any crossover interference? If so, how much?