PATHOLOGY MCQ
GENETICS AND DISEASE
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
Which of the following is the best explanation for the observation that females rarely get the disease hemophilia (an X linked trait)?
|
|
Large quantities of male hormones are necessary in order for the allele carrying the disease to be expressed.
|
|
|
Female fetuses that carry the allele for the disease die before birth.
|
|
|
A female could get the disease only by having a mother who is a carrier and a father who has the disease. Since most males with the disease do not survive to reproductive age, this is an extremely unlikely event.
|
|
|
A female could get the disease only by having parents who are both carriers of the disease. Because females cannot be carriers, this is an impossible event.
|
Explanation:
Detailed explanation-1: -Females may have hemophilia with the same factor VIII (FVIII) or factor IX (FIX) levels as affected males.
Detailed explanation-2: -Hemophilia is a sex-linked recessive disorder. The abnormal gene responsible for hemophilia is carried on the X chromosome. Males have one X chromosome and one Y chromosome.
There is 1 question to complete.