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 Nabhajit Mallik A1 Manu Jamwal A1 Ritika Sharma A1 Namrata Singh A1 Prashant Sharma A1 Deepak Bansal A1 Amita Trehan A1 Sanjeev Chhabra A1 Reena Das YR 2022 UL http://jcp.bmj.com/content/75/11/791.abstract AB