What has happened to the haemophilia gene ?
It seems to have 'bred out'.
A carrier female has a 50% chance of transmitting her haemophilia gene, and so a 50% chance of not transmitting it. If she has a son with the gene he will be a haemophiliac, if a daughter she will have the same 50% chance of passing the gene on each time she has a child.
A male haemophiliac will inevitably pass the gene on to any daughter he has, so that any daughter will be a carrier female, with the 50% chance of passing on the gene.
Someone will no doubt carrect me if I'm mistaken, but as far as I'm aware the only royal haemophiliac who fathered children was Leopold of Albany. His son, Charles Edward of Albany and Coburg, was unaffected. His daughter, Alice of Athlone was a carrier. Her elder son was haemophiliac, her younger son, who died at 6 months, may have been. However, her daughter, May Abel-Smith, was presumably one of the lucky 50%, as haemophilia has not appeared among her descendants.
For the sake of completeness, the royal haemophiliacs I know of are:
Leopold of Albany (son and daughter)
Friedrich of Hesse (died aged 3)
Leopold of Battenberg (lived to adulthood but no children)
Waldemar of Prussia (lived to 56, but no children)
Heinrich of Prussia jnr (died aged 4)
Alexei
Alfonso and Jaime of Spain (both died from car accidents as young adults, no children)
Maurice of Teck, Viscount Trematon (died from car accident aged 21, no children)
The mathematicians on the Forum will no doubt compute the odd, but the risk of passing on the gene haves in each generation from a carrier female, and if a woman is not a carrier and a man is not a haemophliac there is nothing to transmit.
The situation is different with porphyria, which can appear to skip generations because not everyone with the gene is badly affected.
I have read suggestions that a female-line descendant of Victoria of Milford Haven is haemophiliac, but know nothing definite.
Ann
