Answer: B - The change alters the amino acid sequence of the protein.
The change in only one DNA base of the hemoglobin gene can result in a different protein product because the genetic code is highly specific and redundant. The genetic code is a set of rules that specify the correspondence between the nucleotide sequence of DNA and the amino acid sequence of a protein. Each group of three nucleotides, called a codon, codes for a specific amino acid.
A change in a single nucleotide, also known as a single nucleotide polymorphism (SNP), can alter the coding sequence of the gene and, therefore, the amino acid sequence of the protein product. This alteration can result in a different protein with altered function or stability. In some cases, a single nucleotide change can result in a codon that codes for a different amino acid, leading to a substitution of one amino acid for another in the protein. This change in the protein sequence can alter its function, stability, or localization in the cell, leading to a different protein product of the gene.
In the case of hemoglobin, a single nucleotide change can result in a different protein product that may have altered oxygen-binding properties, leading to diseases such as sickle cell anemia or β-thalassemia. Therefore, a single nucleotide change in the hemoglobin gene can have a significant impact on the function and stability of the protein product, resulting in a different protein product of the gene.
