Ank-1^1674/+ mice exhibit profound malarial resistance. (A) Kaplan-Meier cumulative survival plots for male and female wt and Ank-1^1674/+ mice after infection with P chabaudi. P values were determined by log-rank (Mantle-Cox), and less than .05 was considered significant. (B) In vivo red cell survival study in wt and Ank-1^1674/+ mice. The P value was determined using ANOVA and greater than .05 was considered not significant. (C) In vitro invasion of RBCs from wt and Ank-1^1674/+ mice with malaria parasites. (D) OF of red cells from 6-week-old wt, Ank-1^1674/+, and Ank-1^1674/1674 mice. Error bars represent SD in all figures.