Described herein are methods and compositions for the detection of transthyretin (TTR), retinol binding protein (RBP) and retinol complex formation. The methods and compositions described herein also provide for the screening of modulators of retinol-RBP-TTR complex formation. Furthermore, the methods and compositions provide for therapeutic agents for the treatment and/or prevention of age-related macular degeneration and/or dystrophies.