(a) Why is haemophilia generally observed in human males? Explain the conditions under which a human female can be haemophilic.
(b) A pregnant human female was advised to undergo M.T.P. It was diagnosed by her doctor that the foetus she is carrying has developed from a zygote formed by an XX-egg fertilized by Y-carrying sperm. Why was she advised to undergo M.T.P.?
Answers
See.... Haemophilia is an X linked ressecive disorder that means if both the X chromosome carries the gene for haemophilia......it would lead to an affected individual.....
Now males are at a higher risk of having haemophilia because they have only one X chromosome...and if this x chromesome has the defected gene .....it would lead to haemophilia.... females on the other hand have two X chromosomes and both of them should have the defected gene ....for a female to be affected......
A female can only be affected if at least mother is carrier and father is haemophiliac.....
2)this condition would lead to the individual having 47 chromosomes (44+XXY) ...this is called KLINEFELTER syndrome.....sterile males...so it is advisable to abort the baby....