β-thalassemia is a group of heterogeneous autosomal recessive disorders caused by the absence or reduced synthesis of the β-globin chain. Consequently, the excess production of the α-globin chain leads to its precipitation within the red blood cells causing ineffective erythropoiesis. Extensive work in the last two decades has led to the elucidation of the spectrum of these monogenic disorders. Over 200 different mutations leading to β- thalassemia have been characterized worldwide. A varied clinical expression is exhibited by homozygotes and compound heterozygotes. The majority of these mutations are due to small nucleotide substitutions and deletions. However, the mutations are population specific, and common and rare mutations are found in each population. In the Middle East, codon 39 (C > T), IVSI-110 (G > A), IVSI-1 (G > A), IVSI-6 (T > C), IVSII-1 (G >A), codon 5 (-CT) and IVSI-5 (G > C) mutations account for more than 90% of β-thalassemia mutations in the region. However, these mutations differ in number and frequency between the populations of the Middle East. Over fifty different mutations have been identified in the Arab population which reflects the heterogeneity of these populations. In order to prevent transmission of the mutation, carriers of β-thalassemia need to be identified since their offspring are at risk of inheriting the mutation. Therefore, this work will be carried out to study the spectrum of mutations of β-thalassemia prevalent in Al-Ahssa and the surrounding areas.
Patients with β-thalassemia exhibit varying degrees of clinical manifestations and severity. This is attributed to many factors including the type of mutation in the β-globin gene, interaction with the alpha-thalassemia gene or over expression of the fetal hemoglobin gene. Therefore, it is essential that a study should be conducted to assess the relationship between the genotype and phenotype of the disease and to determine whether these genetic determinant factors can predict phenotype severity.
Sickle cell anemia is one of the most serious diseases prevalent in the Al-Ahssa area. It is estimated that one in 500 babies born in Al-Ahssa will develop sickle cell disease. Children with sickle cell anemia tend to be small in stature and below normal weight. This is attributed to an increased demand for energy as a consequence of the progress of the disease. Therefore, it has been postulated that supplementation of these children’s diet with compounds that lower their energy needs will improve their weight and growth and reduce the number of hemolytic crises and duration of hospitalization. One candidate is glutamine. Therefore, this project will study the effect of glutamine in patients with sickle cell anemia.
