[Establishment of a hemophilia B transgenic mouse model on the basis of coagulation factor IX gene knock-out mouse].
This study aimed to introduce a site specific point mutation into the human coagulation factor IX gene expressing vectors (pMe4bAIXml plasmid) for microinjection and to obtain transgenic mouse containing copies of a stably integrated pMe4bAIXml plasmid on the basis of coagulation factor IX gene knock-out mouse model as an more efficient animal model of hemophilia b. The site specific point mutation was introduced into pMe4bAIXml plasmid which consists of human coagulation factor IX gene including the entire coding sequence and a shortened first intron, four copies of the mouse MCK enhancer, chicken beta-actin promotor and poly A signal sequence. The vector was linearized and injected into 817 fertilized eggs of mice in which coagulation factor IX gene has been knocked out. The manipulated embryos were transferred into the oviducts of 45 pseudopregnant females, from which 63 offsprings were obtained. The genomic DNAs of these offsprings were analyzed with PCR and genomic Southern blotting. Six mice were found to carry copies of the intact pMe4bAIXml plasmid containing a point mutation and used as founders to establish transgenic mouse lineages.