If a mother has one dominant allele for a disease on her X chromosome, what is the likelihood her sons and daughters will inherit the disease?
Question
If a mother has one dominant allele for a disease on her X chromosome, what is the likelihood her sons and daughters will inherit the disease?
Solution
The likelihood of a son or daughter inheriting a disease from a mother with one dominant allele on her X chromosome depends on whether the disease is X-linked or not.
-
If the disease is X-linked:
- Sons: A son has a 50% chance of inheriting the disease. This is because sons receive their X chromosome from their mother and their Y chromosome from their father. If the son receives the X chromosome carrying the dominant allele for the disease, he will have the disease.
- Daughters: A daughter has a 50% chance of being a carrier of the disease. This is because daughters receive one X chromosome from their mother and one X chromosome from their father. If the daughter receives the X chromosome carrying the dominant allele for the disease from the mother, she will be a carrier. However, she will typically not express the disease unless it is a dominant trait and the father also carries the allele for the disease on his X chromosome.
-
If the disease is not X-linked:
- Both sons and daughters have a 50% chance of inheriting the dominant allele for the disease from their mother. However, whether they express the disease depends on the allele they inherit from their father and whether the disease is a dominant or recessive trait.
Similar Questions
If a man has an X-linked recessive disorder, he will transmit the mutant allele to all sons, but to no daughters.Group of answer choicesTrueFalse
Which allele combination represents a male who has an X-linked recessive disorder?
In order for a female to have an X-linked recessive disorder, both her mother and father must have it.Group of answer choicesFalseTrue
It requires only one affected allele in order to express that trait.Group of answer choicesautosomal dominant disorderautosomal recessive disorderNext
On a pedigree diagram of an X-linked recessive disorder, males and females are affected with equal frequency.Group of answer choicesFalseTrue
Upgrade your grade with Knowee
Get personalized homework help. Review tough concepts in more detail, or go deeper into your topic by exploring other relevant questions.