Chapter 8, Problem 22P

The human $\text{β-globin}$ wild-type allele and a certain mutant allele are identical in sequence except for a single base-pair substitution that changes one nucleotide at the end of intron $\text{2}$. The wild-type and mutant sequences of the affected portion of $\text{pre-mRNA}$ are

a. Speculate about the way in which this base substitution causes mutation of $\text{β-globin}$ protein.

b. This is one example of how DNA sequence change occurring somewhere other than in an exon can produce mutation. List other kinds of DNA sequence changes occurring outside exons that can produce mutation. In each case, characterize the kind of change you would expect to see in mutant mRNA or mutant protein.