Question

In Belted Galloways; Black (B), belted (H), and polled (P) alleles are dominant to red (bb), solid (hh), and horned (pp). What are the genotypic and phenotypic frequencies for a matting of BbHhPP x BBHhPp?

Answer 1

When BbHhPP * BBHhPp which are the parental genotypes, with BBHhPP-Black, Belted and Polled phenotype and BBHhPp- Black, Belted and Polled Phenotype in a trihybrid cross.

When we allow them to mate we have the following gametes. We have eight gametes from each parent.

Number of gametes can be calculated by raising number two (number of parents) with number of alles. alleles here are 3.

So, = 2 * 2 * 2 = 8.

BbHhPP * BBHhPp ----- Crossed

	BHP	BHp	BhP	Bhp	BHP	BHp	BhP	Bhp
BHP	BBHHPP Black, Belted,Polled	BBHHPp Black, Belted,Polled	BBHhPP Black, Belted,Polled	BBHhPp Black, Belted,Polled	BBHHPP Black, Belted,Polled	BBHHPp Black, Belted,Polled	BBHhPP Black, Belted,Polled	BBHhPp Black, Belted,Polled
BHP	BBHHPP Black, Belted,Polled	BBHHPp Black, Belted,Polled	BBHhPP Black, Belted,Polled	BBHhPp Black, Belted,Polled	BBHHPP Black, Belted,Polled	BBHHPp Black, Belted,Polled	BBHhPP Black, Belted,Polled	BBHhPp Black, Belted,Polled
BhP	BBHhPP Black, Belted,Polled	BBHhPp Black, Belted,Polled	BBhhPP Black, Solid,Polled	BBhhPp Black, solid, polled	BBHhPP Black, Belted,Polled	BBHhPp Black, Belted,Polled	BBhhPP Black, solid, polled	BBhhPp Black, Solid Polled
BhP	BBHhPP Black, Belted,Polled	BBHhPp Black, Belted,Polled	BBhhPP Black, Solid, Polled	BBhhPp Black, solid, Polled	BBHhPP Black, Belted,Polled	BBHhPp Black, Belted,Polled	BBhhPP Black, solid, polled	BBhhPp Black, solid, polled
bHP	BbHHPP Black, Belted,Polled	BbHHPp Black, Belted,Polled	BbHhPP Black, Belted,Polled	BbHhPp Black, Belted,Polled	BbHHPP Black, Belted,Polled	BbHHPp Black, Belted,Polled	BbHhPP Black, Belted,Polled	BbHhPp Black, Belted,Polled
bHP	BbHHPP Black, Belted,Polled	BbHHPp Black, Belted,Polled	BbHhPP Black, Belted,Polled	BbHhPp Black, Belted,Polled	BbHHPP Black, Belted,Polled	BbHHPp Black, Belted,Polled	BbHhPP Black, Belted,Polled	BbHhPp Black, Belted,Polled
bhP	BbHhPP Black, Belted,Polled	BbHhPp Black, Belted,Polled	BbhhPP Black, solid, polled	BbhhPp Black, solid, polled	BbHhPP Black, Belted,Polled	BbHhPp Black, Belted,Polled	BbhhPP Black, solid, polled	BbhhPp Black, solid, polled
bhP	BbHhPP Black, Belted,Polled	BbHhPp Black, Belted,Polled	BbhhPP Black, solid, polled	BbhhPp Black, solid, polled	BbHhPP Black, Belted,Polled	BbHhPp Black, Belted,Polled	BbhhPP Black, solid, polled	BbhhPp Black, solid, polled

We have,

Phenotypic Ratio :

1 : 1 - Black, Belted and Polled : Black, Solid and Polled.

Phenotypic frequency is Black,Belted and Polled - 56 /64 and Black,Solid and Polled is 8/64.

Black, Solid and Polled are highlighted in red color.

Genotypic Ratio: 4 : 4 : 8 : 8 : 4 : 4 : 4 : 4 : 8 : 8 : 4 : 4.

Genotypic Frequencies : 4/64 , 4/64, 8/64, 8/64, 4/64, 4/64, 4/64, 4/64, 8/64, 8/64, 4/64, 4/64.

BBHHPP- 4 - 4/64.

BBHHPp-4 - 4/64.

BBHhPP-8 - 8/64.

BBHhPp-8 - 8/64.

BBhhPP-4 - 4/64.

BBhhPp-4 - 4/64.

BbHHPP-4 - 4/64.

BbHHPp-4 - 4/64.

BbHhPP-8 - 8/64.

BbHhPp-8 -8-64.

BbhhPP-4 -4/64.

BbhhPp-4 - 4/64.