PMM2 and congenital disorder of glycosylation: Hypocholesterolemia may also manifest in other disorders, including abetalipoproteinemia types I and II, chylomicron retention disorder, PMM2‐congenital disorder of glycosylation, mevalonic aciduria, 3β‐hydroxy‐Δ5‐C27 steroid dehydrogenase deficiency, Smith–Lemli–Opitz syndrome, and Tangier disease.12, 13