Females are carriers of Haemophilia. Give Reason.

Explanation

Haemophilia is a disease caused by a recessive X - linked gene. If a normal female marries a colour blind male or vice versa, the gene is carried in the X - chromosome of the female (female has 2 X Chromosomes). If both the chromosomes carry the receive gene she becomes colour blind. If one X chromosome caries the recessive gene she may not suffer from the disease but will be a carrier carrying the gene to the next generation. Haemophilia follows the characteristics criss - cross pattern of inheritance. The females are carries of the disease and world transmit the disease to 50% of thier son's even if a male parent is normal.