Open AccessHaemoglobin Olympia {β Codon 20 (B2) G→A, Val→Met}: A Silent Haemoglobin Variant
Author(s) -
Abhay Bhave,
Lakshmi Rani Iyer,
Nawal Kazi,
Manju Gorivale,
Anita Nadkarni
Publication year - 2021
Publication title -
journal of clinical and diagnostic research
Language(s) - English
Resource type - Journals
eISSN - 2249-782X
pISSN - 0973-709X
DOI - 10.7860/jcdr/2021/47560.14677
Subject(s) - proband , etiology , family history , methionine , pediatrics , valine , medicine , mutation , genetics , biology , gene , amino acid
High oxygen affinity haemoglobin variants are rare and often underdiagnosed in persistent erythrocytosis with no apparent aetiology. Here the author present a 29-year-old Indian male patient with a long-standing history of erythrocytosis which was incidentally detected. The proband had a prothrombotic family history of cerebral vessel stroke in his paternal grandfather at a young age and unexplained erythrocytosis in his father and brother. A review of his haemograms showed persistent high haemoglobin values. Routine tests did not reveal any specific aetiology and haemoglobin electrophoresis by High-Performance Liquid Chromatography (HPLC) showed absence of any abnormal peak or unstable haemoglobin. DNA sequencing of the β globin gene revealed heterozygosity for codon 20 {GTG→ATG, Valine (Val)→ Methionine (Met)} mutation confirming the presence of an electrophoretically silent Hb variant - Haemoglobin Olympia in him and his extended family members. This case study emphasises importance of this rare entity of high oxygen affinity haemoglobin variant as a differential diagnosis while screening for erythrocytosis. This is the first case report of Haemoglobin Olympia from India reported in the literature.