Of note, Fancd2 null mutant mice exhibit a variety of phenotypes, including reduced body size, some degree of abnormal germ cells, eye abnormalities an increased incidence of tumors such as adenomas, and anemia, mirroring the anemia found in human FA patients (Houghtaling et al. 2003; Parmar et al. 2010; Yang et al. 2019). This evidence concerns the gene FANCD2 and Friedreich ataxia.