Question

Famously, Queen Victoria’s descendants were plagued by haemophilia, an X-linked recessive disease. The present day monarch of the United Kingdom, Queen Elizabeth, is a direct descendent of Queen Victoria: Elizabeth’s great grandfather was Victoria’s son (King Edward VII) who was not a haemophiliac. What is the chance that Elizabeth is a carrier for haemophilia? Explain your reasoning

**i know not all infomation is provided but the answer is apprenently avaliable within that infomation.**

Answer 1

There is a 50% chance that Queen Victoria will be a carrier of haemophilia as she is a direct descendant of Queen Elizabeth so there is 50% chance of getting the affected X chromosome.

Her father did not have hemophilia that means his X chromosome was not affected. So, she will not get affected X chromosome from his father.

So, in all there is 50% probability of getting diseased chromosome from the mother.

So, there are 50% chances of being a carrier of haemophilia.