HbD Punjab/HbQ India Compound Heterozygosity: An Unusual Association.
Mediterr J Hematol Infect Dis 2014;
6:e2014072. [PMID:
25408858 PMCID:
PMC4235469 DOI:
10.4084/mjhid.2014.072]
[Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2014] [Accepted: 10/18/2014] [Indexed: 11/21/2022] Open
Abstract
Background
Haemoglobinopathies are the commonest hereditary disorders in India and pose a major health problem. Both beta thalassaemia and structural haemoglobin variants are relatively common in northwestern India. Here we report a 29-year-old Sindhi female who was referred to us for a haemoglobinopathy work up and genetic counseling since her spouse was a classical beta thalassaemia carrier.
Method
A complete blood count was done on an automated cell counter. Haemoglobin analysis was carried out using HPLC Variant Haemoglobin Testing System. The cellulose acetate electrophoresis was carried out [pH 8.9]. Confirmation of mutations was done by automated DNA sequencing.
Results
HPLC analysis showed four major peaks, HbA0, a peak in the HbD window, an unknown peak [retention time 4.74 minutes] and a peak in the HbC window. The HbA2 level was 2.2%, and the HbF level was 0.7%. Cellulose acetate electrophoresis at alkaline pH, a slow moving band was seen at the HbS/D position along with a prominent band at the HbA2 position. DNA sequencing of the β and α genes showed presence of the two hemoglobin variants: Hb D [β 121GAA → CAA] and Hb Q [α 64 AAG → GAG]. The δ globin gene was normal. The additional peak in the HbC window was due to the formation of a heterodimer hybrid.
Conclusion
Both HbD Punjab and HbQ India are relatively common in India, but their co-inheritance has not been described in the country. This case is the third report of compound heterozygosity for HbQ India/HbD Punjab haemoglobinopathy globally and the second one from India.
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