TGFBR2 and age-related macular degeneration: Bialas and Steven have observed that Tgfbr2–/– animals had a deficient expression of complement protein C1q (which has been associated with AMD), and both Tgfbr2–/– and C1q deficient (C1qa–/–) animals had reduced rates of RGC phagocytosis compared to age-matched controls (Bialas and Stevens, 2013).