The Full Wiki

Haemophilia B: Wikis


Note: Many of our articles have direct quotes from sources you can cite, within the Wikipedia article! This article doesn't yet, but we're working on it! See more info or our list of citable articles.

Did you know ...

More interesting facts on Haemophilia B

Include this on your site/blog:


From Wikipedia, the free encyclopedia

Haemophilia B
Classification and external resources
ICD-10 D67.
ICD-9 286.1
OMIM 306900
DiseasesDB 5561
MedlinePlus 000539
eMedicine emerg/240
MeSH D002836

Haemophilia B (also spelled Hemophilia B or Hæmophilia B) is a blood clotting disorder caused by a mutation of the Factor IX gene, leading to a deficiency of Factor IX. It is the less common form of haemophilia, rarer than haemophilia A. It is sometimes called Christmas disease after Stephen Christmas, the first patient described with this disease.[1] In addition, the first report of its identification was published in the Christmas edition of the British Medical Journal.[2]



Treatment (bleeding prophylaxis) is by intravenous infusion of factor IX. Factor IX has a longer half life than factor VIII (Deficient in Haemophilia A) and as such factor IX can be transfused less frequently.


The factor IX gene is located on the X chromosome (Xq27.1-q27.2). It is an X-linked recessive trait, which explains why, as in haemophilia A, only males are usually affected. 1 in 50,000 males are affected.


Factor IX deficiency leads to an increased propensity for haemorrhage. This is in response to mild trauma or even spontaneously, such as in joints (haemarthrosis) or muscles.

British and Russian Royal Families

A study published in 2009 identified the blood disease affecting both the Russian (Romanov) and British Royal Families as haemophilia B on the basis of genetic markers.[3][4]


  1. ^ Christmas' disease at Who Named It?
  2. ^ Biggs R, Douglas AS, MacFarlane RG, Dacie JV, Pitney WR, Merskey C, O'Brien JR (1952). "Christmas disease: a condition previously mistaken for haemophilia". Br Med J 2 (4799): 1378–82. PMID 12997790.  
  3. ^ Michael Price (8 October 2009). "Case Closed: Famous Royals Suffered From Hemophilia". ScienceNOW Daily News. AAAS. Retrieved 9 October 2009.  
  4. ^ Evgeny I. Rogaev et al. (8 October 2009). "Genotype Analysis Identifies the Cause of the "Royal Disease"". Science. Retrieved 9 October 2009.  

See also

External links

Got something to say? Make a comment.
Your name
Your email address