Which of these causes sickle-cell anemia?(1 point)
too few chromosomes
too many chromosomes
base pair substitution***
base pair deletion
To determine which of these options causes sickle-cell anemia, we need to understand the underlying cause of the condition. Sickle-cell anemia is a genetic disorder that affects the shape of red blood cells.
The correct answer is base pair substitution. Sickle cell anemia is caused by a specific mutation in the gene that codes for hemoglobin, the protein responsible for carrying oxygen in red blood cells. This mutation involves a substitution of a single base pair of DNA. Specifically, a nucleotide called adenine is replaced by thymine in the gene sequence.
To arrive at this answer, knowledge of genetics and the specific mutation associated with sickle-cell anemia is required. Genetic analyses, such as DNA sequencing techniques or genetic testing, can confirm the presence of this specific base pair substitution in an individual with sickle-cell anemia.