Principles of Inheritance and Variation Question 8

8. A woman has an X-linked condition on one of her $X$ chromosomes. This chromosome can be inherited by

(a) Only daughters

(b) Only sons

(c) Both sons and daughters

(d) Only grandchildren

Show Answer

Answer : c

Hints & Solution

(c) Woman acts as a carrier. Both son & daughter inherit X-chromosome. Although only son would be the diseased one. Sex-linked diseases are passed down through families through one of the $X$ or $Y$ chromosomes. $X$ and $Y$ are sex chromosomes. Dominant inheritance occurs when an abnormal gene from one parent causes disease, even though the matching gene from the other parent is normal.