Tyrosine phosphatase

Runting
Splenomegaly
Lymphodenopathy
Defect in bone marrow
Defect in B cell lymphopoiesis
Defect in erythropoiesis
Impaired T and B cell function
Death by 3-5 weeks of age

Reference:

You-Ten KE, Muise ES, itie A., Michaliszyn E., wagner J., Jothy S., Lapp WS, Tremblay ML.: Impaired bone marrow microenvironment and immune function in T cell protein tyrosine phosphatase-deficient mice. J Exp Med 1997 Aug;186 (50):683-693.