Human adult hemoglobin is a tetramer containing two alpha (α) and two beta (β) polypeptide chains. The α gene cluster on chromosome 16 and the β gene cluster on chromosome 11 share amino acid similarities such that 61 of the amino acids of the α-globin polypeptide (141 amino acids long) are shared in identical sequence with the β-globin polypeptide (146 amino acids long). How might one explain the existence of two polypeptides with partially shared function and structure on two different chromosomes?

Video transcript

Hey, everyone. Let's take a look at this question together. The H B B gene is the gene that provides instruction for the production of beta globe in which is an important component of hemoglobin. The shortage of beta globe in production prevents the formation of functional hemoglobin. The condition in which there is an absence of beta globe in is referred to as what. So we know that hemoglobin is composed of four protein subunit. And so we have to alpha Globe in sub units and we also have two beta globe in sub units. And so when we're talking about that HBV gene, specifically when we have mutations in the gene. So we have mutations in H B B, we end up with something called beta Alice E MIA. And when we're talking about a mutation in Beta Globe and production that leads to that absence of the beta globe in we have a mutation that causes an absence. It is called beta zero fallacy mia or answer choice B. The correct answer because we know that hemoglobin is comprised of four protein sub units. We have two alpha globe in sub units and two beta globe in sub units. And when we have that mutation in that H B B gene, we end up with beta thalassemia. And the mutation that causes that absence of the beta globe ins protein subunits is called beta zero thalassemia or answer choice. B. The correct answer, I hope you found this video to be helpful. Thank you and goodbye.