Question 3 (6 pts). In hogs, colored hair (H) is completely dominant to colorles

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Question 3 (6 pts). In hogs, colored hair (H) is completely dominant to colorless (h) and bent tails (B) are completely dominant to straight tails (b). There are no interlocus interactions. Penetrance and expressivity are 100%. The two loci are not sex-linked. The phenotypes and frequencies of progeny following testcrosses of hogs 1 and 2 to a double recessive genotype (hh bb) are listed in the table:

Phenotype

Testcross

Progeny of hog 1

Testcross

Progeny of hog 2

colored, bent

134

28

colored, straight

11

335

colorless, bent

12

358

colorless, straight

143

30

TOTALS

300

751

For testcross progeny of hog 1, what are the recombinant classes or recombinant phenotypes in the progeny?

For testcross progeny of hog 2, what are parental classes or parental phenotypes in the progeny?

For hog 2, are the recessive alleles in the cis or trans configuration?

(2 pts) How far apart (in cM) are the two gene loci on the genetic map? You can use data from progeny of hog 1 or hog 2. Show your work.

For hog 1, If the two loci were sorting or segregating independently, what fraction of the testcross progeny would you expect to have colored hair and straight tails

Phenotype

Testcross

Progeny of hog 1

Testcross

Progeny of hog 2

colored, bent

134

28

colored, straight

11

335

colorless, bent

12

358

colorless, straight

143

30

TOTALS

300

751

Explanation / Answer

For the test cross of progeny of hog1coloured bent and colourless straight are the recombinant type, where as these are the parental type in hog2.

For determination of distance of two gene:

distance between 2 gene is 3.6+ 4 = 7.6

For hog 1, if the two loci were sorting or segregating independently the all type of progeny are produced in 1:1:1:1 ratio i.e 25% fraction have expect to have colored hair and staight tils

% frequency % frequncy colored bent 134 44.6 28 3.7 colored straight 11 3.6 335 44.6 colorless bent 12 4 358 47.6 colorless straight 143 47.6 30 3.9

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