Figure 7. The Sl2 allele is associated with reduced ex vivo rosette frequency of P. falciparum clinical isolates.

Parasite isolates were collected from 167 malaria patients in Mali and matured in culture for 18–36 hr before assessment of rosette frequency (percentage of infected erythrocytes forming rosettes with two or more uninfected erythrocytes). Red bars show the median rosette frequency and interquartile range (IQR) for each genotype. (A) Rosetting by patient Sl genotype. Sl1/Sl1 (n = 22, median 20.0, IQR 8.3–36.5), Sl1/Sl2 (n = 82, median 4.0, IQR 0–20.3), Sl2/Sl2 (n = 63, median 5.0, IQR 0–17.0); *p<0.05, Kruskal Wallis with Dunn’s multiple comparison test; (B) Rosetting by McC genotype. McC^a/McC^a (n = 81, median 9.0, IQR 0–22.0), McC^a/McC^b (n = 73, median 6.0, IQR 0–20.0), McC^b/McC^b (n = 13, median 4.0, IQR 1–14.5); not significant, Kruskal Wallis with Dunn’s multiple comparison test.