Affects the rate of fibrils formation. May have a primary role in collagen fibrillogenesis (By similarity). Binds to type I and type II collagen. Binds keratan sulfate chains. Incorrect gene name (LUM) has been attributed by Ref.1. LUM and FMOD are two different genes but members of the same family. Belongs to the small leucine-rich proteoglycan (SLRP) family. SLRP class II subfamily.