The Ampd3^T689A mutation shortens erythrocyte lifespan. (A) Amount of bilirubin in the plasma of WT, Ampd3^T689A/+ and Ampd3^T689A mice. Black bars indicate median. (B) RBC half-life in WT, Ampd3^T689A/+ and Ampd3^T689A mice, as measured by loss of biotinylated cells from circulation. (C) RBC half-life in splenectomized WT, Ampd3^T689A/+, and Ampd3^T689A as measured by loss of biotinylated cells from circulation. (C) Amount of nonheme iron (in duplicate) in the spleen of WT (n = 2), Ampd3^T689A/+ (n = 2), and Ampd3^T689A (n = 4). Black bars indicate median. (D) Osmotic fragility of WT, Ampd3^T689A/+, and Ampd3^T689A (all genotypes n = 3). (F) Amount of lysis for WT, Ampd3^T689A/+ and Ampd3^T689A cells incubated in vitro at 37°C for 24 hours, measured by absorbance at 545 nm, and compared with 100% lysis. Values are mean ± SEM. *P < .05; ***P < .001. P values calculated using the Student t test.