Female flies homozygous for gray body blk and red eyes v wer

Female flies homozygous for gray body (blk^+) and red eyes (v^+), were crossed with male flies with black body (blk) and vermilion eye colour (v). All the F_1 generation had gray bodies and red eyes. The F1 females were testcrossed to black-bodied, vermilion-eyed males. The F2 progeny were sorted by phenotype and counted: 162 gray-bodied, red-eyed flies; 149 black-bodied, vermilion-eyed flies; 77 gray-bodied, vermilion-eyed flies; and 72 black-bodied, red-eyed flies. Calculate the frequency of recombination.

Solution

Frequency of recombination = [Number of recombinant / (Number of recombinant +Number of Parental )] * 100

Recombinant types = gray bodied,vermilion eyed flies = 77 and black bodies ,red eyed flies = 72 : Total = 149

Parental types = gray bodied,red eyed flies = 162 and black bodied ,vermilion eyed flies = 149 :Total = 311

Frequency of recombination = [149 / (149+311 )*] 100 = 32.4 % (ans )