A 21-year-old woman comes to the physician for an annual health maintenance examination. She has no particular health concerns. Laboratory results obtained during today's visit are as follows: The patient's blood smear is shown in the image below. Which of the following processes is the initial step in the pathogenesis of this patient's disorder?

Question

A 21-year-old woman comes to the physician for an annual health maintenance examination. She has no particular health concerns. Laboratory results obtained during today's visit are as follows:  The patient's blood smear is shown in the image below.  Which of the following processes is the initial step in the pathogenesis of this patient's disorder?

Quizplus · Accepted Answer

Eductional Objective: Beta-thalassemia is caused by mutations that result in defective transcription, processing, and translation of beta-globin mRNA. Small nuclear ribonucleoproteins (snRNP) are the subunits of spliceosomes, which are required for proper processing of pre-mRNA (hnRNA). Spliceosomes remove the introns from pre-mRNA through specific splicing sites encoded in introns (AG at the 3' end and GU at the 5' end). Mutations in the intronic splice site of the Beta-globin locus result in improper splicing, which leads to expression of abnormal Beta-globin. This leads to deficiency of the beta-globin chains required for normal hemoglobin synthesis.

A 21-Year-Old Woman Comes to the Physician for an Annual