Similar protective effect in the 0’s group was observed in the analysis of recurrent anemia where the risk of anemia seen in at least 4 cycles of treatment for the carriers of two independent risk factors could arise from slower detoxification rate and drugs accumulation (ALDH3A1, p.Pro329Ala) and from simultaneous alterations in efflux by the multidrug transporter (ABCB1, p.Ile1145=). The gene discussed is ALDH3A1; the disease is anemia.