Question

There are normally four total α-globin alleles present on chromosome 16, two per chromosome. How many α-globin alleles are present on each chromosome?

1) One
2) Two
3) Three
4) Four

Answer 1

There are two α-globin alleles on each chromosome 16, for a total of four alleles across the two chromosomes. Conditions like α-thalassemia affect the synthesis of these globin chains, which are crucial for the structure of different forms of hemoglobin.

Step-by-step explanation:

The student asks how many α-globin alleles are present on each chromosome 16. Given that there are normally four total α-globin alleles on chromosome 16, with two per chromosome, the answer to the student’s question is two. This is because each pair of chromosomes carries their own set of genes, resulting in two α-globin alleles per chromosome 16.

α-thalassemia is a condition where there is a decreased rate of synthesis of the α-chain of globin, which is part of the hemoglobin molecule. Various forms of hemoglobin, including HbA (normal adult hemoglobin with 2α and 2β chains), HbA2 (minor adult hemoglobin with 2α and 2δ chains), and HbF (fetal hemoglobin with 2α and 2γ chains), reflect the different combinations of globin chains.