FANCC and Friedreich ataxia: To quantify precursor number in a mouse model of FA, we generate Fancc+/+, Fancc+/−, and Fancc−/− mice with a single Confetti allele and homozygous HSC-SCL-CreERT alleles (HSC-SCL-CreERT/TRosa26+/ConfettiFancc+/+, hereafter Fancc+/+; HSC-SCL-CreERT/TRosa26+/ConfettiFancc+/−, hereafter Fancc+/−; HSC-SCL-CreERT/TRosa26+/ConfettiFancc−/−, hereafter Fancc−/−) (Chen et al., 1996).