Hemoglobin Titusville [α2 Codon 94 G>A]: A Rare Alpha Globin Chain Variant Causing Low Oxygen Saturation

Wide spectrum of novel and rare hemoglobin variants in the multi‐ethnic Indian population: A review

“…Hemoglobin J Norfolk [α 2 or α 1 Codon 57 (G→A)] [HBA2:c.173G>A (or HBA1)] was identified for the first time in a 23‐year‐old female originating from Maharashtra, during routine screening 17 . Hemoglobin Titusville [α 2 or α 1 Codon 94 (G→A)] [HBA2:c.283G>A (or HBA1)] was reported for the first time in India by Dasgupta et al 18 A 31‐year‐old female from Tamil Nadu presented with low oxygen saturation during cesarean section. On further investigations, the patient and her mother showed an abnormal peak in the Hb S window on HPLC.…”

“…Some rare variants co‐elute with common ones like HbE and HbS. Hb Titusville, Hb Shimonoseki, Hb Chandigarh, Hb D Agri, Hb Yaizu, Hb Rush and Hb Vellore eluted in the HbS window on HPLC 18,20–22,38,39,51 . A negative sickling/solubility test is a useful pointer to the possibility of another variant rather than HbS and should always be done.…”

“…1 Hemoglobin variants such as Hb Jackson, Hb J Norfolk, Hb Titusville, Hb Shimonoseki, Hb Acharnes, Hb Fannin-Lubbock I, Hb British Columbia, Hb Pyrgos, Hb Limassol, Hb Ty Gard, Hb Mckees Rocks, HbC, Hb Alperton, HbG Waimanalo and Hb Brugg are rare variants seen in other countries but reported for the first time from India. 7,17,18,20,23,30,32,33,36,37,50,55,57,58 Hb Ty Gard is a high oxygen affinity hemoglobin reported twice from France. 1 Hb Alpertonβ-thalassemia was clinically severe.…”

“…18,[20][21][22]38,39,51 A negative sickling/ solubility test is a useful pointer to the possibility of another variant rather than HbS and should always be done. Hb Titusville is a low oxygen affinity hemoglobin and was first identified in a female child of African American origin.…”