Huntington Disease is an autosomal recessive condition. Which percentage shows the genotype probability when a female with Huntington disease
mates with a male that is heterozygous for the Huntington trait? *
A.
B.
hh
hh
Hh
hh
Hh
C.
D.
Hh
HH

The options to this question are unclear but the answer is: Hh, Hh, hh, hh i.e Hh (50%), hh (50%).

Explanation:

This question involves a single Gene coding for the possession or not of Huntington's disease in humans. The disease is said to be an autosomal recessive condition i.e. it only happens in a recessive state (hh).

According to this question, when a female with Huntington disease (hh) mates with a male that is heterozygous (Hh) for the Huntington trait, the following gametes will be produced by each parent.

hh - h and h

Hh - H and h

Using these gametes in a punnet square (see attached image), the following genotypic combination of offsprings will be produced.

Hh, Hh, hh and hh

Hh = 50%

hh = 50%

Huntington Disease is Which percentage

shows the genotype probability  *

p

explanation: