Wednesday 9 December 2009

Royal blood disorder identified


Scientists have discovered that the so-called 'Royal disease' that afflicted Queen Victoria's descendants was a very rare form of haemophilia. By analysing the degraded DNA (deoxyribonucleic acid) taken from the bones of what are believed to be the last children of Russian Tsar, Nicholas II, scientists at the University of Massachusetts, US, discovered a mutation occurring in F9 on the X chromosome responsible for the production of Factor IX, a clotting agent. A malfunction in this production is the cause of haemophilia B.

Termed 'Christmas disease,' after Stephen Christmas who suffered from the disease in the 50s, haemophilia B affects one in 20,000-34,000 males, according to The Times newspaper. The disorder is passed through the maternal line but it only manifests itself in males, as they only have one X chromosome. It would be very rare for a female to be more than a carrier of the mutation as both X chromosomes would need to be affected.

Dr Evgeny Rogaev, who led the study published in the journal Science, commented, 'We have resolved a medical mystery from the past.' Although it was known that Queen Victoria's descendants suffered from a blood-clotting disorder, it was not known exactly what the condition was. In the publication the authors explain that: 'We identified the likely disease-causing mutation by applying genomic methodologies (multiplex target amplification and massively parallel sequencing) to historical specimens from the Romanov branch of the royal family.' The 'Royal disease' is now extinct, say the authors, but it was passed across the Royal families throughout Europe including Spain and Russia. It is believed the disorder originated spontaneously from Queen Victoria, whose son, Leopold, died after bleeding from a fall. The Times explained that whereas nowadays patients with haemophilia B are given synthetic clotting agents, back in 1905 Tsarina Alexandra turned to the infamous 'psychic' Rasputin.

Tsar Nicholas II and his family were murdered during the Russian Revolution in 1918. It was since believed that two of his children may have escaped, Alexei and Anastasia, but their bones were discovered in the Ural mountains in 2007. Subsequent testing confirmed the identity of the remains and that they too had been murdered.

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