Question

Three different crosses in yeast are analyzed. Each cross combined a different pair of genes. The results are as follows: 30 Cross Parents Parental types Tetratypes Non-parental ditypes Total Number 1 A B x a bl 30 40 100 2 CDXcd 60 30 100 3 EF Xef 40 60 10 10 10 a. Which pair of genes is linked? What is the recombination frequency between them? Submission type: • Submit entries below as answer to receive credit O Save entries below (not submitted for credit yet) Rich formatting >> Submit Answer Tries 0/99 b. Which pair of genes segregates independently in meiosis? Submission type: • Submit entries below as answer to receive credit O Save entries below (not submitted for credit yet) Rich formatting » Submit Answer Tries 0/99 c. Which pair of genes is linked to the centromere? Submission type: Submit entries below as answer to receive credit O Save entries below (not submitted for credit yet) Rich formatting »

Answer 1

a) 1.ABx ab= recombination frequency ={ non-parental Ditype(NPD)+1/2(Tetrad)}/ total no. Of progeny = 30+ 1/2x 40/100= 50%

2.CDxcd=recombination frequency= (10+1/2x30)/100=25%

3.EFx ef=recombination frequency (10+1/2x40)/60= 50%

So only 2 cross genotype is linked as it has below than 50%

b) both cross of perental type 1 and parental 3 has recombination frequency is 50%

C) cross1 is linked to centromere.

Hope it's clear..thanks