Question

Genes A, B, and C are linked on a chromosome and found in the order A-B-C. Genes A and B recombine with a frequency of 9%, and genes B and C recombine at a frequency of 22%. For the cross

a ⁺b ⁺c/abc⁺ × abc/abc,
predict the frequency of progeny. Assume interference is zero.

a)Predict the frequency of a⁺b⁺c progeny.

Enter your answer to four decimal places (example 0.2356 or 0.2300).

B) Predict the frequency of abc⁺progeny.

Enter your answer to four decimal places (example 0.2356 or 0.2300)

Part C

Predict the frequency of a⁺bc⁺progeny.

Enter your answer to four decimal places (example 0.2356 or 0.2300)

Part D

Predict the frequency of ab⁺c progeny.

Enter your answer to four decimal places (example 0.2356 or 0.2300)

Part E

Predict the frequency of a⁺b⁺c⁺ progeny.

Enter your answer to four decimal places (example 0.2356 or 0.2300)

Part F

Predict the frequency of abc progeny.

Enter your answer to four decimal places (example 0.2356 or 0.2300)

Part G

Predict the frequency of a⁺bc progeny.

Enter your answer to four decimal places (example 0.2356 or 0.2300)

Predict the frequency of ab⁺c⁺progeny.Part H

Enter your answer to four decimal places (example 0.2356 or 0.2300)

Answer 1

A). The frequency of a⁺b⁺c progeny= 0.3549

B)Tthe frequency of abc⁺progeny = 0.3549

C) The frequency of a⁺bc⁺progeny = 0.0351
D) The frequency of ab⁺c progeny = 0.0351

E) The frequency of a⁺b⁺c⁺ progeny = 0.1001

F) The frequency of abc progeny = 0.1001

G) The frequency of a⁺bc progeny = 0.0099

H). The frequency of ab⁺c⁺progeny = 0.0099

Explanation:

Class of gametes	Phenotype	Frequency of reciprocal pair	Numbers	Frequency of each class
Parental	a+ b+ c	1- all recombinant progeny	1-(0.0702+0.2002+0.0198) = 0.7098	0.3549
	a b c+			0.3549
SCO 1	a+ b c+	RF in region 1 = SCO1 - DCO	SCO1 = 0.09 – 0.0198 = 0.0702	0.0351
	a b+ c			0.0351
SCO 2	a+ b+ c+	RF in region 2 = SCO2 - DCO	SCO2 = 0.22 – 0.0198 = 0.2002	0.1001
	a b c			0.1001
DCO	a+ b c	(RF in region 1) * (RF in region 2)	0.09 * 0.22 = 0.0198	0.0099
	a b+ c+			0.0099