Background
Members of the LDL receptor gene family, including LDLR (low density lipoprotein receptor), LRP1 (low density lipoprotein related protein), Megalin (also designated GP330), VLDLR (very low density lipoprotein receptor) and ApoER2 are characterized by a cluster of cysteine-rich class A repeats, epidermal growth factor (EGF)-like repeats, YWTD repeats and an O-linked sugar domain. LRP11 (low density lipoprotein receptor-related protein 11), also known as MANSC3, is a 500 amino acid single-pass type I membrane protein that exists as 2 alternatively spliced isoforms. LRP11 is encoded by a gene located on human chromosome 6q25.1. Chromosome 6 contains 170 million base pairs and comprises nearly 6% of the human genome. Deletion of a portion of the q arm of chromosome 6 is associated with early onset intestinal cancer, suggesting the presence of a cancer susceptibility locus. Additionally, Porphyria cutanea tarda, Parkinson’s disease, Stickler syndrome and a susceptibility to bipolar disorder are all associated with genes that map to chromosome 6.