RT Journal Article SR Electronic T1 Ultra-rare Hb Regina (HBB:c.289C>G) with coinherited β-thalassaemia trait: solving the puzzle for extreme erythrocytosis JF Journal of Clinical Pathology JO J Clin Pathol FD BMJ Publishing Group Ltd and Association of Clinical Pathologists SP 791 OP 792 DO 10.1136/jclinpath-2021-208013 VO 75 IS 11 A1 Mallik, Nabhajit A1 Jamwal, Manu A1 Sharma, Ritika A1 Singh, Namrata A1 Sharma, Prashant A1 Bansal, Deepak A1 Trehan, Amita A1 Chhabra, Sanjeev A1 Das, Reena YR 2022 UL http://jcp.bmj.com/content/75/11/791.abstract AB