A man who is an achondroplastic dwarf with normal vision marries a color-blind woman of normal height. The man's father was six
feet tall, and both the woman's parents were of average height. Achondroplastic dwarfism is autosomal dominant, and red-green color blindness is X-linked recessive. They have a daughter who is a dwarf with normal color vision. What is the probability that she is heterozygous for both genes?
The autosomal dominant trait means that the trait is visible in homozygous dominant and in heterozygous condition. The X linked recessive trait will be pass down from mothers to their sons and daughters will show the trait in homozygous recessive condition only.
The man is achandroplastic dwarf ( Aa) with normal vision (XY ) is married with woman that has normal height (aa) with color blind (XhXh). They have a daughter who is dwarf ( Aa). The probability of being dwarf can be calculated by the cross Aa × aa. The offspring are Aa, Aa, aa, aa. Means 1/2 are the probability of being hetterozygous for achondroplastic . The vision probability is calculated by cross XY and XhXHh. The probability that female is heterozygous is 1/2.
So, the heterozygous probability for both trait is 1/2× 1/2 = 1/4.
The most common type of skin cancer is basal
cell carcinoma. Basal cell carcinoma <span>produces an open ulcer and
can be easily treated with radiation therapy or surgical removal.
</span>Malignant melanoma on the other hand, is
known to be<span> the most
aggressive and life-threatening of all types of skin cancer.</span>
