Complement factor H (CFH), a critical regulator of the complement activity, is a large glycoprotein encode by the CFH gene. In humans, five genes (CFHR1, CFHR2, CFHR3, CFHR4, and CFHR5) are found telomerically adjacent to the CFH gene and encode five different complement factor H related (CFHR) proteins. These five CFHR proteins are divided into two major groups based on their conserved domains: Group I (CFHR1, CFHR2, and CFHR5) and Group II (CFHR3 and CFHR4). Learn more: CFHR2 Protein