A Novel Hemoglobin Variant Associated with Congenital Erythrocytosis: Hb Seoul [β86(F2)Ala→Thr] (HBB:c.259G>A).
We report the identification of a novel hemoglobin (Hb) variant [β86(F2)Ala→Thr; HBB: c.259G>A], Hb Seoul, causing congenital erythrocytosis due to high oxygen affinity. The patient was a 33-year-old Korean man with isolated erythrocytosis. JAK2 somatic mutations were negative. Direct sequencing analyses revealed that the patient was heterozygous for c.259G>A, while other known causative genes (BPGM, EGLN1, EPAS, EPOR and VHL) had no mutation. β86(F2) is a critical residue that affects the oxygen affinity. The novel variant in our patient, Hb Seoul, adds to the previously reported 4 other Hb variants from β86(F2) substitutions that cause congenital erythrocytosis.
Department of Laboratory Medicine & Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Sang-Yong
SY
Shin
Department of Internal Medicine, Seoul National University Bundang Hospital, Seongnam, Korea.
Soo-Mi
SM
Bang
Department of Laboratory Medicine & Genetics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea heejinkim@skku.edu.
Hee-Jin
HJ
Kim
D000328:Adult; D000595:Amino Acid Sequence; D019943:Amino Acid Substitution; D001483:Base Sequence; D006455:Hemoglobins, Abnormal / Q000737:chemistry / Q000235:genetics*; D006801:Humans; D008297:Male; D011086:Polycythemia / Q000151:congenital* / Q000235:genetics*; D055544:beta-Globins / Q000737:chemistry / Q000235:genetics*
D006455:Hemoglobins, Abnormal; D055544:beta-Globins
Congenital erythrocytosis; HBB; Hb Seoul; Variant hemoglobin (Hb)