An HBB Intron 1 Variant (c.92 + 9C > T) Suggestive of β-Thalassemia Trait

We describe the identification of an intronic variant in the β-globin gene (HBB: c0.92 + 9C > T) in a 41-year-old Spanish male presenting with microcytosis and hypochromia in the absence of iron deficiency. This variant, located in intron 1 of the HBB gene, was identified using the Devyser Thalassemia NGS kit and confirmed by Sanger sequencing. In silico predictions suggest potential splicing disruption. The hematological profile was consistent with β-thalassemia trait, although Hb A2 values were within normal ranges. This variant is not reported in public databases and is currently classified as of uncertain significance with moderate pathogenic potential according to ACMG criteria. This discrepancy between bioinformatic predictions and clinical classification is discussed. The variant has been submitted to both HbVar and IthaGenes databases (submission ID pending). This report contributes to the expanding catalog of HBB variants and underscores the diagnostic relevance of intronic regions.