Table 1.

Characterization and proposed classification of BRCA2 SyVaL clones

CloneRAD51MMCEtoposideChromosomal instabilityClassification
BRCA2wt/Δex11Pos (16.7 ± 1.5/59.0 ± 0.7)No ΔNo ΔNegNeutral
BRCA2Δex11/Δex11Neg (2.5 ± 0.8/3.3 ± 2.8)20-fold Δ10-foldPosDeleterious *
BRCA2Δex11/Y3308XNeg (1.8 ± 0.5/1.6 ± 0.3)20-fold Δ10-foldDeleterious
BRCA2Δex11/Y3308YPos (12.4 ± 0.6/34.1 ± 1.1)No ΔNo ΔNeutral
BRCA2Δex11/P3292LPos (13.6 ± 2.4/41.6 ± 4.7)No ΔNo ΔNeutral
BRCA2Δex11/P3280HPos (12.2 ± 1.3/41.7 ± 4.5)No ΔNo ΔNeutral
BRCA2Δex11/S3291ENeg (3.6 ± 0.6/12.4 ± 0.9)3-fold Δ3-fold ΔHypomorphic
BRCA2Δex11/S3291APos (23.8 ± 4.1/47.6 ± 9.7)No ΔNo ΔNeutral
  • NOTE: Numbers in parentheses represent mean percentage of untreated/treated cells with more than five RAD51 foci ± SE. Fold Δ refers to the ratio of the IC50 of cells having the hemizygous wt allele to the IC50 of cells having the mutated allele.

    Abbreviations: Pos, positive; Neg, negative; —, not done; Δ, change.

  • * The extreme rarity of knockout clones may indicate an especially severe deleterious effect ( 21).