In a particular kind of plant wildtype individuals have purp

In a particular kind of plant, wild-type individuals have purple flowers. Recessive mutations in the b gene result in blue flowers. Recessive mutations in the w gene result in white flowers. The w mutation is epistatic to b. A purple-flowered plant heterozygous for both b and w was test-crossed with a white-flowered plant homozygous for the recessive alleles of both genes. The actual results obtained from the cross described were as follows: 40 purple flowers, 10 blue flowers, and 50 white flowers. What is the genetic distance between b and w?

Solution

Answer:

Recombinance frequency (%) = Distance between the gene(cM)

Recombination frequency = (Number of recombinant progeny/Total progeny) * 100

Parental phenotypes are purple and white= 40+50- 90

Recombinant phenotyp is blue= 10

Total progeny= 100

RF= (10/100)*100

RF= 10%

The distance between the genes, b & w is 10cM