Although the results of the present study should be taken with caution because the previously discussed limitations, and deserve a confirmation with further replication studies in other populations, they suggest a slightly increased risk for MS in Spanish Caucasian men carrying the HMOX2 rs1051308A allele variant, and a trend towards association between the HMOX1 rs2071746A and MS risk. The gene discussed is HMOX1; the disease is myeloid sarcoma.