Fig. 1.

Inbreeding protocols for generating 30–50 G3 mice with ENU-induced mutations. Mutagenized G0 males are bred to G0′ females carrying germ-line mutations derived from other mutagenized males (A) or to WT C57BL/6J (B6) females (B). G1 males are crossed to B6 females to produce G2 mice. G3 mice result from backcross of G2 females to their G1 father. G3 mice are subjected to screening. Asterisks represent mutations derived from the G0 male (red) and G0′ female (blue); larger asterisks indicate initial germ-line transmission of the mutation. (C) Timeline for G3 mouse production, genotyping, and screening.