A three point testcross was made in corn. The alleles C and c result in colored versus colorless seeds, Wx and

Question

wx in nonwaxy versus waxy seeds, and Sh and sh in plump versus shrunken seeds. When plants grown from seeds heterozygous for each of these pairs of alleles were testcrossed, the progeny were as follows.

colorless, nonwaxy, shrunken 84
colorless, nonwaxy, plump 974
colorless, waxy, shrunken 20
colorless, waxy, plump 2349
colored, waxy, shrunken 951
colored, waxy, plump 99
colored, nonwaxy, shrunken 2216
colored, nonwaxy, plump 15


Determine: a) the genotype of the heterozygous parent, b) the order of the three genes, c) the genetic distance between each gene and d) calculate interference.

Answer 1

I remember something like this in biology

I am not going to do your homework for you, but you start by finding the percentages of phenotypes

Answer 2

i have just done this,

i used a book called igenetics it was a great help.

you need to work out your number of progeny first, then group them so parental combinations, single cross-over and double cross overs.

it is easy when you get the hang of it