Table 1.

Phenotypes of mouse models with modified JAK1 signaling.

Mouse model	Targeting?	Genes modified	Phenotype	References
Jak1−/−	Germline	JAK1 deletion	Embryonic lethal, stunted embryos	27
MMTV‐Cre.Jak1fl/fl	Germline	JAK1 deletion	Embryonic lethal, stunted embryos	28
Tofacitinib treatment	Systemic	JAK1/3 inhibition	Protected against localized bone resorption caused by inflammation. Possible systemic protection against elevated resorption caused by inflammation.	31–33
Ruxolitinib treatment	Systemic	JAK1/2 inhibition	Protected against age-related bone resorption.	34
Jak1S645P+/−	Germline	JAK1 activation	Adult trabecular and cortical bone mass levels were both low due to elevated bone formation and resorption, indicating secondary systemic lupus erythematosus-like symptoms.	48