The allele b gives Drosophila flies a black body, and b+ gives brown, the wild-type phenotype....

The allele b gives Drosophila flies a black body, and b+ gives brown, the wild-type phenotype. The allele wx of a separate gene gives waxy wings, and wx+ gives nonwaxy, the wild-type phenotype. The allele cn of a third gene gives cinnabar eyes, and cn+ gives red, the wild-type phenotype. A female heterozygous for these three genes is testcrossed, and 2,424 progeny (you could also use n=2,423) are classified as follows:

cn+ · wx+ · b 101

cn · wx+ · b+ 768

cn · wx+ · b 20

cn+ · wx+ · b+ 323

cn+ · wx · b 848

cn · wx · b+ 101

cn · wx · b 242

cn+ · wx · b+ 20

Calculate the recombinant frequencies for b-wx, b-cn, and wx-cn.

Which gene is in the middle: b, wx, or cn?

Screen shot of table in case of formatting issues:

NOTE: the genotypes in the table below were released on Friday July 10, but there are errors which have been corrected above.

cn+ · wx · b 101

cn · wx+ · b+ 768

cn · wx · +b 20

cn+ · wx+ · b+ 323

cn+ · wx · b 848

cn · wx · b 101

cn · wx+ · b 242

cn+ · wx · b 20

Expert Solution

Answer-

A) gene b is in the middle.

B) recombinant frequency between b-wx = 9.99% ; cn-b = 24.97% ; cn-wx = 33.3%

The calculation is given below:

gladiator answered 7 months ago

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