We also mapped a micronucleus QTL at this locus, that contains only three genes within its 95% CI, including Slc7a1. Mice carrying a homozygous deleterious mutation of this gene die of anemia at birth with 50% fewer red blood cells and reduced hemoglobin levels (Perkins et al. 1997). This evidence concerns the gene SLC7A1 and anemia (phenotype).