From 129 to C57BL/6 Congenic

B6129F3 ♂ -/- x C57BL/6 ♀ +/+ = B6129N1 100% +/-

B6129N1 ♀ +/- x C57BL/6 ♂ +/+ = B6129N2 25% +/-

B6129N2 ♂ +/- x C57BL/6 ♀ +/+ = B6129N3 25% +/-

B6129N3 ♂ +/- x C57BL/6 ♀ +/+ =  B6129N4 25% +/-

B6129N4 ♂ +/- x C57BL/6 ♀ +/+ = B6129N5 25% +/-

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B6.129N10 ♂ +/- x B6.129N10 ♀ +/- = B6.129N10F1 25% -/-

B6.129N10F1 ♂ -/- x B6.129N10F1 ♀ -/- = B6.129N10F2 100% -/-

B6.129N10F2 -/- congenics are suitable for study on defined genetic background.