Percentages of CD38⁺/CD5⁺/CD19⁺ cells among mutated and unmutated B-CLL cases. The percentages of CD38-expressing B-CLL cells among patients (n = 37) whose Ig V_H and V_L genes had been sequenced. Unmutated cases (⧫) display <2.0% differences from the most similar germline gene; mutated samples (⋄) display ≥2% differences. Note that all of the cases (17 of 17) that have ≥30% CD38⁺ B-CLL cells were unmutated, whereas only 3 unmutated cases expressed low numbers (<30%) of CD38⁺ B-CLL cells. These comparisons are statistically significant (P = .00001; Mann-Whitney test).