HPS1 and albinism: Among the 10 human HPS subtypes and the corresponding mouse subtypes with similar albinism phenotypes, it has been reported that hps1 gene mutations are most often responsible for HPS in humans, with deficiency of the mouse ortholog causing a similar phenotype (Oh et al. 1996; Gardner et al. 1997; Wei 2006; Huizing et al. 2020).