ALDH single nucleotide polymorphisms (SNP) (ALDH1A2: rs4646626, ALDH3A1: rs2228100, ALDH3A1: rs887241 and ALDH16A1: rs1320303) were genotyped using tetra-primer-ARMS-PCR, in 99 MN patients (49 MDS patients and 50 AML patients), and in 118 control individuals. The gene discussed is ALDH3A1; the disease is myelodysplastic syndrome.