Identification of seven novel variants in the β-globin gene in transfusion-dependent and normal patients.

Introduction: Abnormality in results in an inherited recessive blood disorder, which can be caused by variants at the transcriptional or translational level affecting the stability and the production of the HBB chain. The severity of the disease relies on the variant's characteristics. This study aimed to identify the common β-globin variants in the population of the Eastern Province, which has the highest prevalence of blood diseases in Saudi Arabia.

Material And Methods: Direct sequence of β-globin gene, and alpha-globin and genes was performed on a total of 545 blood samples (transfusion-dependent: 215, 106 men and 109 women; normal healthy subjects: 330, 197 men and 133 women) collected from Saudi Arabian participants in the Eastern region.

Results: A total of 36 variants in gene were revealed with 11 variants that have been reported for the first time in Saudi Arabia, including 7 novel variants that have been identified for the first time in gene. The novel variants consisted of two exonic (HBB:c.252C>T; HBB:c.281G>T) and five intronic variants (c.316-183_316-168del; c.315+241T>A; c.315+376T>C; c.316-114C>G; c.315+208T>G) at gene. The novel exonic variants and three (c.316-183_316-168del; c.315+241T>A; c.315+376T>C) intronic variants were co-inherited with α deletion.

Conclusions: This current study updated the gene variations with newly identified variants of gene and co-inheritance with α-globin deletions. The identified β-globin mutations will strengthen the genetic reference that could aid in characterizing mutations that are associated with phenotype of thalassemia in a specific region.