Comparison of variable region gene family usage for anti-Rh(D)–specific clones with those used by randomly picked, non-Rh(D)-binding clones from original γ₁κ and γ₁λ unselected libraries. Lightly hatched bars reveal heterogeneity in V_H (left panel), V_κ (middle panel), and V_λ (right panel) family representation before selection for anti-Rh(D) specificity. Numbers above bars represent absolute number of clones in that group.