Molecular Identification and the Hematological Findings of Four Novel Variants in Globin Genes in Jiangxi Province of Southern China

Abstract

Hemoglobin disorders are highly prevalent inherited hematological defects in Southern China. The identification of novel variants in globin genes and accurate assessment of hematological parameters play a crucial role in precise genetic counseling and clinical practice. Peripheral blood samples were collected for hematological analysis, including red blood cell and hemoglobin assessment, while serum ferritin levels were measured to detect iron depletion. Thalassemia carrier identification was conducted in four subjects admitted to Jiangxi Maternal and Child Health Hospital using next-generation sequencing and Gap-PCR due to the high prevalence of thalassemia in Jiangxi Province. The identified rare or novel small nucleotide variants were subsequently validated through Sanger sequencing. A total of four novel variants were identified incidentally in four unrelated subjects, including HBA1: c.300G > C (p.Lys100Asn), HBA2: c.212T > A (p.Val71Glu), HBB: c.28T > A (p.Ser10Thr) and c.167T > C (p.Met56Thr). The proband carrying the c.212T > A and c.300G > C variants exhibited normal hematological findings, while capillary electrophoresis revealed the presence of abnormal hemoglobin fractions at 22.4% and 10.9%. The subjects with variant HBB: c.28T > A and c.167T > C all demonstrated normal hematological findings and normal hemoglobin fraction as determined by capillary electrophoresis or ion exchange high-resolution liquid chromatography (HPLC). The two variants exhibiting abnormal fractions of hemoglobin were designated as Hb Jiangxi (HBA2: c.212T > A) and Hb Fulton (HBA1: c.300G > C). Meanwhile, HBB: c.28T > A and HBB: c.167T > C were referred to as Hb Yichun and Hb Jinxian, respectively. We here reported four novel variants in globin genes and their hematological findings in for unrelated Chinese individuals in Southern China. Our research has expanded the existing genetic spectrum of globin genes and enhanced our understanding of the hematological profiles associated with variant hemoglobin.