Hemoglobin Trait Variant Sickle Cell Syndrome Dominant Sickle Cell Disease None SCDO (Jade Hotchkiss) Often these individuals have co-inherited another hemoglobin mutation that decreases hemoglobin solubility (eg, HbS-Antilles; Hb-Quebec-Chori; HbS-Oman; Hb Jamaica Plain). Other rare causes of symptomatic sickle cell trait include: mosaicism for cells in which only the sickle mutation was expressed due to post-zygotic uniparental disomy, and when sickle cell trait coexists with pyruvate kinase deficiency, which lowers the hemoglobin oxygen affinity, resulting in hemoglobin S polymerization and sickling. Dominant Sickle Syndrome Hemoglobin Jamaica Plain is an example of an abnormal hemoglobin structure caused by a double mutation in 1 Hb allele. Dominant Sickle Cell Syndrome Clinical sickle cell disease in the heterozygous state due to an additional mutation on the same allele as the beta S mutation.