Molecular and haematological characterisation of haemoglobin G-Georgia: a case series from Terengganu, Malaysia
DOI:
https://doi.org/10.63719/imrj.2026.12.02.007Keywords:
Haemoglobinopathy, Alpha Variant, Hb G-GeorgiaAbstract
Haemoglobin G-Georgia (HBA1:c.287C>T) is a rare and benign alpha globin chain variant with amino acid substitution of Proline to Leucine in the alpha gene. Hb G-Georgia was initially documented in an African American male in 1970, its occurrence in Malaysia was first characterised in 2015 in a patient of Malay ethnicity. This is a cross-sectional retrospective laboratory-based study describing the haematological parameters, clinical phenotypes, and genotypic profiles of 12 individuals with Hb G-Georgia from the state of Terengganu in Malaysia from the year 2017 to 2022 based on results from the full blood count, haemoglobin analysis, and molecular analysis. Twelve cases of Hb G-Georgia in the heterozygous state, compound heterozygous state of Hb G-Georgia with deletional alpha thalassaemia and in co-inheritance of Hb G-Georgia with heterozygous Hb E (HBB:c.79G>A) were reported. Hb G-Georgia is predominantly linked to mutations in the HBA2 gene. However, all documented cases within the Malaysian cohort occurred on the HBA1 gene, explaining the measured Hb G-Georgia proportions of 8.9% to 10.6%. All cases identified in Terengganu were clinically asymptomatic, consistent with the benign nature of Hb G-Georgia. Comprehensive molecular characterization and mapping of local genetic variants offer critical insights into the population-specific spectrum of haemoglobin disorders, ultimately enhancing carrier detection, risk assessment, and genetic counselling.
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Copyright (c) 2026 Suguna Somasundram, Yuslina Mat Yusoff, Ezalia Esa, Siti Nurrazan Zulkifli, Ermi Neiza Mohd Sahid, Azian Naila Md Nor, Wan Zuhairah Wan Embong, Wan Amal Hayati Wan Hassan, Azly Sumanty Ab Ghani, Syahzuwan Hassan, Faidatul Syazlin Abdul Hamid, Nur Aisyah Aziz, Ezzanie Suffya Zulkefli, Ulfatul Khusna Samuri, Norafiza Mohd Yasin (Author)
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