Age-dependent changes in the relative sizes of the precursor B-cell subsets. (A) The relative size of the precursor B-cell subsets (given in percentages) was statistically significant different from healthy controls: *P < .01, ***P < .001 by nonparametric t test. (B) Statistically significant age-dependent increases or decreases were observed in the percentage pre-B-I, pre-B-II, and immature B cells of NBS patients. In healthy controls, only a statistically significant age-dependent increase was observed in the percentage immature B cells.