Question

The human B-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 2 (inside the intron). a) Speculate about the way in which this base substitution causes a mutation of the B-globin protein.

Answer 1

B-globin protein

Step-by-step explanation:

The base substitution will affect the splicing mechanism

• Base substitution is a type of mutation that exchange one nucleotide base for another,for example A gets substituted by G
• Such a substitution change a codon to one that encodes a different amino acid and cause a small change in the protein produced
• Beta globin is a single chain of 147 amino acids and is a component (subunit) of a larger protein called hemoglobin, which is located inside red blood cells
• In adults, hemoglobin normally consists of four protein subunits: two subunits of beta-globin and two subunits of another protein called alpha-globin, which is produced from another gene called HBA
• Of the mutations leading to qualitative alterations in hemoglobin mutation in the β-globin gene that causes sickle cell anemia is the most common
• The mutation causing sickle cell anemia is a single nucleotide substitution (A to T) in the codon for amino acid 6,this change converts a glutamic acid codon (GAG) to a valine codon (GTG)