H2AX and systemic lupus erythematosus: Specifically, study of the formation of N-alkylpurine-monoadducts (almost exclusively repaired by NER) at the N-ras (neuroblastoma RAS) locus, the repair rate of which is representative of the total cellular NER capacity, and phosphorylated H2AX (γ-H2AX), a sensitive marker for DNA DSBs that was measured at the level of the whole cell, revealed that SLE patients with nephritis have approximately 3–5 times higher intrinsic DNA damage compared with healthy controls.