UBAC2 (ubiquitin-associated domain-containing protein 2), also known as PHGDHL1 (phosphoglycerate dehydrogenase-like protein 1), is a 344 amino acid multi-pass membrane protein that contains one UBA domain and is expressed as multiple alternatively spliced isoforms. The gene encoding UBAC2 maps to human chromosome 13, which houses over 400 genes, such as BRCA2 and RB1, and comprises nearly 4% of the human genome. As with most chromosomes, polysomy of part or all of chromosome 13 is deleterious to development and decreases the odds of survival. Trisomy 13, also known as Patau syndrome, is deadly and the few who survive past one year suffer from permanent neurologic defects, difficulty eating and vulnerability to serious respiratory infections.