PCSK9 and hypercholesterolemia, autosomal dominant, 3: LDLR degrades by PCSK9 through suppression of the hairpin structural modification of LDLR.54,55 Additional variants are associated with an uncommon autosomal dominant familial hypercholesterolemia (HCHOLA3) disease.56,57 Its protease activity is boosted by mutations, the amount of LDLR is reduced, and LDL cholesterol will not be absorbed into the cells.56 PCSK9 protein in human first undergoes transformation and settle down within the brain.