C1QTNF1 and age-related macular degeneration: A statistically significant difference between the groups was observed in the case of the C1qTNF1 protein; patients with AMD had a significantly higher expression than the healthy control group (5.14 ± 0.34 NPX [normalized protein expression] vs. 4.91 ± 0.38 NPX, p = 0.02.