Question

Why would a mutation at a splice site result in a defective beta globin gene when introns are spliced out anyway?

a) It affects the transcription process.
b) It disrupts the translation process.
c) It alters the exon order.
d) It impacts protein folding.

Answer 1

A splice site mutation can cause an altered beta globin gene because it may lead to incorrect splicing, including or excluding exons and introns incorrectly, which affects protein folding and can result in genetic disorders like beta-thalassemia.

Step-by-step explanation:

A mutation at a splice site can result in a defective beta globin gene, despite introns being spliced out, because it may disrupt the normal splicing process. Under normal circumstances, splicing involves the precise removal of introns and the joining of exons to form a mature mRNA transcript. If a mutation occurs at a splice site, the splicing machinery might improperly recognize the boundaries of the introns, leading to the exclusion of exons or inclusion of parts of introns in the final mRNA. This can lead to an altered amino acid sequence and disrupt the protein folding, ultimately impacting gene expression. Such mutations may lead to various genetic disorders, including beta-thalassemia, which is characterized by mutations in the beta-globin gene affecting the synthesis of hemoglobin.