Hereditary diseases such as Haemophilia are caused by:

Haemophilia has featured prominently in European royalty and thus is sometimes known as 'the royal disease'.

Haemophilia is a mostly inherited genetic disorder that impairs the body's ability to clot, a process needed to stop bleeding. In this inherited disorder, your blood lacks one of several clot-forming proteins. This results in people bleeding for a longer time after an injury, easy bruising, and an increased risk of bleeding inside joints or the brain.

In almost 70 percent of cases, hemophilia is inherited. If a woman carries the defective gene in one of her X-chromosomes, her children, both male and female, have a 50 percent chance of inheriting it. If a carrier woman has a daughter and she inherits the faulty gene from her mother, she also will be a carrier. However, if a carrier woman has a son who inherits the faulty gene, he will develop the disease.