|| “royal disease” also known as hemophilia B or Christmas disease
|| Royal Disease Hemophilia B SNP
is a SNP in the coagulation factor IX F9
gene, in an intron just upstream of the fourth exon. The F9 gene is on the X chromosome.
In 2009, researchers sequenced bones from the remains of the Nicholas II Romanov family, who were killed in 1918. This family harbored a form of hemophilia known as the “royal disease,” transmitted from Queen Victoria (1819–1901) to European royal families. The sequencing revealed the SNP responsible for their hemophilia, also known as hemophilia B or Christmas disease, to be rs398122990. To be specific, as an X-linked recessive disease, males (such as Prince Alexei) inheriting a rs398122990(G) allele and females inheriting two copies would be hemophiliacs, while rs398122990(A;G) females were unaffected carriers (as was Queen Victoria).[PMID 19815722]
On the suggestion of a Finnish researcher, in 2014 SNPedia submitted this SNP to dbSNP to have it assigned the rs-identifier you now see. It is currently unknown if this "royal disease" rs398122990(G) SNP is extinct world-wide, i.e. no longer present even in a single unaffected carrier somewhere in the world. If through the use of Promethease or other tools this allele, rs398122990(G), is identified in a human genome sequence derived from a living person, please contact us!
This SNP is referred to as i5007022 by 23andMe.