Updates in Beta Thalassemia

**15**

**Chapter 2**

**Abstract**

chelators, HSCT

**1. Introduction**

**1.1 Updates in diagnosis**

*1.1.1 Preimplantation genetic diagnosis*

Updates in Thalassemia

genetic counseling, carrier detection, and prenatal diagnosis.

**The most important indications of PGD [1] are:**

• monogenic disorders, e.g., Thalassemias;

• HLA matching (savior baby);

• cancer predisposition; and

• sex discernment.

Beta-thalassemia is a genetic disease caused by mutations in the β-globin gene, resulting in partial or complete deficiency of β-chain. Deficiency of β-chain was accompanied by excess unmatched α-globin chains with subsequent dyserythropoiesis, oxidative stress, and chronic anemia. The main therapeutic option is blood transfusion that improves the anemic status but unfortunately exacerbates iron overload status. Till now, the only curative measure is allo-hematopoietic stem cell transplantation. New diagnostic and therapeutic modalities are now available. These include the preimplantation genetic diagnosis and new tools in the assessment of iron overload. Also, new therapeutic options aimed at different targets are being developed; for example, therapies that stimulate the synthesis of γ-globin and reduce the synthesis of α-globin, as well as the iron excess, dyserythropoiesis, and oxidative stress. However, the most likely ideal approach is efficient prevention, through

**Keywords:** β-thalassemia, genetic diagnosis, gene therapy, gene editing, new iron

Prenatal diagnosis (PND) services are the best practices to control prevalence of disease. Wide spread practicing of PND proved effective in reducing the number of new cases but on the other hand high abortion rate is hided, which ethically unaccepted and for many couples is not a suitable choice. Preimplantation genetic diagnosis is considered in a similar fashion to prenatal diagnosis (PGD) and is a strong alternative to conventional PND. PGD means genetic profiling of embryos prior to implantation (embryo profiling). Its main advantage is that it avoids selective pregnancy termination as the method makes it highly likely that the baby will be free of the disease under consideration. At present PGD is the only abortion free fetal diagnostic process [1].

*Tamer Hassan and Marwa Zakaria*
