Pseudogene locations. Chromosomal distribution of GAPDH pseudogenes in the human genome. Pseudogenes are marked by triangles. The parent genes are marked by solid circles, occuring on human chromosomes 12 and 19 (spermatogenic), chimpanzee chromosomes 12 and 19 (spermatogenic), mouse chromosomes 6 and 7 (spermatogenic), and rat chromosome 1 (spermatogenic) and 4. The tick marks along the right edge of a chromosome mark 20 million base pair intervals, starting from the top.