Effect of lineage depletion on single-donor predominance. Two sets of double cord transplantations were performed with lineage-depleted cord blood pairs having 5 or 6 mismatches. Shown are results as analyzed by PCR-SSOP for the DRB1 locus using allele-specific probes (DR5 for CB22 and CB32, DR4 for CB40), where CB22, CB40, or CB32 represents single cord transplantation and CB22/40 or CB32/40 represents double cord transplantation; numbers below represent numbers of mice (n = 6).