HMOX2 and essential thrombocythemia: Therefore, in this study, we selected 12 SNPs (HMOX1 rs2071746, HMOX2 rs4786504, HMOX2 rs1051308, VDR rs731236, IL17A rs8193036, IL1B rs1143643, IL1B rs1143634, IL1B rs1143633, NOS1 rs693534, NOS1 rs7977109, ADH1B rs6413413 and ADH1B rs1229984) within seven suspected RLS risk genetic loci (HMOX1, HMOX2, VDR, IL17A, IL1B, NOS1 and ADH1B), which had not been tested in Chinese ET patients yet, to further investigate the relationship of these genetic risk factors with ET in Chinese population.