Summary of breeding GATA-1^low mutants with normal DBA/2, C57BL/6, and CD1 mice. For the purpose of this study, the contribution of each parental background to the genotype of the offspring was calculated under the assumption that each parent contributed 50% of the alleles and that the effect of crossing-over events to the allelic transmission was negligible. Crossings that do not follow Mendelian inheritance are indicated in gray. The results represent the summary of at least 20 to 30 matings for each crossing.