Editing Factor IX (section)

== Genetics ==
[[File:F9 gene location.png|thumb|In human, the F9 gene is located on the [[X chromosome]] at position q27.1.]]
Because the [[gene]] for factor IX is located on the [[X chromosome]] (Xq27.1-q27.2), loss-of-function mutations thereof are [[X-linked recessive]]: males experience the disease phenotype much more frequently than females. At least 534 disease-causing mutations in this gene have been discovered.<ref name = "Šimčíková_2019 - supplementary table S7">{{cite journal | vauthors = Šimčíková D, Heneberg P | title = Refinement of evolutionary medicine predictions based on clinical evidence for the manifestations of Mendelian diseases | journal = Scientific Reports | volume = 9 | issue = 1 | pages = 18577 | date = December 2019 | pmid = 31819097 | pmc = 6901466 | doi = 10.1038/s41598-019-54976-4| bibcode = 2019NatSR...918577S }}</ref> The F9 gene was first cloned in 1982 by Kotoku Kurachi and [[Earl Davie]].<ref>{{cite journal | vauthors = Kurachi K, Davie EW | title = Isolation and characterization of a cDNA coding for human factor IX | journal = Proceedings of the National Academy of Sciences of the United States of America | volume = 79 | issue = 21 | pages = 6461–4 | date = Nov 1982 | pmid = 6959130 | pmc = 347146 | doi = 10.1073/pnas.79.21.6461 | bibcode = 1982PNAS...79.6461K | doi-access = free }}</ref>

[[Polly and Molly|Polly]], a transgenic cloned [[Poll Dorset]] sheep carrying the gene for factor IX, was produced by Dr [[Ian Wilmut]] at the [[Roslin Institute]] in 1997.<ref>{{cite book |author=Nicholl D. |title=An Introduction to Genetic Engineering Second Edition | publisher=Cambridge University Press |page=257 |year=2002}}</ref>