A number of different types of mutations in the HBB gene can cause human β-thalassemia, a disease characterized by various levels of anemia. Many of these mutations occur within introns or in upstream noncoding sequences. Explain why mutations in these regions often lead to severe disease, although they may not directly alter the coding regions of the gene... Answer: Mutations in introns may affect RNA splicing. Mutations in upstream sequences may disrupt transcription factors. Mutations in introns may affect mRNA stability or translation.
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Mutations in introns can affect RNA splicing. During the process of RNA splicing, introns are removed from the pre-mRNA, and exons are joined together to form the mature mRNA. If a mutation occurs within an intron, it may disrupt the splicing process, leading to Show more…
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