Biochemical Investigation Limits in Recognizing Some Abnormal Hemoglobin Types: Hemoglobins O Arab And S

Abstract

Hemoglobinopathies are a major health problem worldwide. These disorders are characterized by a variable clinical and hematological situation related to a phenotypic heterogeneity. Moreover, in order to have an exact correlation between the biochemical picture and the genetic defect associated with it, it is useful and often indispensable the molecular study of alpha and beta globin genes. The present case report concerns a pregnant woman of Moroccan ethnicity who came to our observation to undergo combined first-trimester testing useful for screening of major chromosomal aneuploidies. Study of hemoglobins A, A2, and F by High performance liquid chromatography (HPLC) revealed the presence of a proportion of abnormal hemoglobin associated with hemoglobin S. Molecular investigation of globin genes excluded that the biochemical variant in question was related to hemoglobin S. In fact, molecular investigation of beta globin genes, found that the observed variant was due to the presence of a genetic defect leading to hemoglobin O Arab synthesis. Evidence suggests that molecular analysis of globin genes provides the most effective and correct way to correlate the detected biochemical picture with its associated genetic defect. The only biochemical study in the presented case determines an incorrect clinical evaluation with consequent inaccurate prognosis. The mutation detected in this work can be identified using a simple and inexpensive kit. This would generate, in economic terms, significant savings associated with a correct diagnosis.