An efficient reproductive method for Irs2^-/- mice with C57BL/ 6JJcL genetic background

Efficient reproduction using natural mating and reproduction technology [in vitro fertilization (IVF) and embryo transfer (ET)] was investigated in IRS2 deficient mice with C57BL/6JJcl genetic background (Irs2^-/- mice) as atypical type 2 diabetes model. From the results using various combinations of Irs2^-/- and Irs2^-/+ mice, the combination of female Irs2^-/+ x male Irs2^-/- was found to be more efficient than other combinations. In applications of reproduction technology using IVF and ET the combination of female Irs2^-/+ x male Irs2^-/- involves the possibility of Irs2^-/- production by repeats using female Irs2^{-/ +} mice. However, reproductive continuity using this combination is difficult because of dependence on human technique and the cost of ET. Therefore, we concluded that Irs2^-/- mice should be produced by embryo transfer using Irs2^-/- mice from a colony consisting of female Irs2^-/+ x male Irs2^-/-.