A Gene Mutation Ameliorates the Severity of -Thalassemia: A Case Report.

Patients with the β/β type of β-thalassemia (β-thal) usually present as β-thal major (β-TM), and are transfusion-dependent. However, the clinical and hematological features of β-thal can be modulated by different modifiers, resulting in a wide range of clinical severity even in patients with the same genotypes. We report a Chinese family with twin brothers, both of whom had the same genotype of β/β. One twin was diagnosed as β-TM at 4 months of age and had regularly been transfused; conversely the other twin with a () gene mutation, behaved as β-thal intermedia (β-TI), and had never been transfused. Our findings indicate that mutations have a role in modulating the phenotypic severity of β-thal. The exact investigation of modifiers is necessary in areas where globin gene disorders are most prevalent. This will be helpful in genetic counseling and optimizing the guidelines for prenatal diagnosis (PND) programs.