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Hemoglobin HBB2 Team International

Hemoglobin HBB2

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Hemoglobin HBB2Team International

Abstract

Hemoglobin is a protein found in humans and various other organisms. In most organisms it is present in, its primary function which is transport of oxygen in blood is similar. Sickle cell disease is a result of the mutation of hemoglobin B (a form of hemoglobin protein). We hypothesize that if hemoglobin B is conserved within animals, then they can possibly develop sickle cell anemia.

Abstract

This hypothesis was explored in by analyzing several Old and New World organisms with the BLAST, Muscle and Phylip databases. We generated phylogenetic trees and found that chimpanzees and orangutans were most closely related to humans. We also found no evidence suggesting that mutation of the hemoglobin B protein in them led to Sickle Cell Anemia.

Introduction

Hemoglobin is a protein encapsulated in red blood cells (Shechter, 2008). It’s primary function is the transportation of oxygen in blood not only in humans but various organisms in which hemoglobin is also present (Remington, et al 2008). A mutation of hemoglobin B which is a form of the hemoglobin protein in which the red blood cell becomes sickle shaped results in a disease called Sickle Cell disease. In-depth research has been done on this disease as it is rampant amongst many human populations. Some symptoms of the disease include difficulty in breathing, dizziness and pain among others in humans (Browning, et al 2006).

Introduction

As hemoglobin is present in other organisms and has similar functions in them, Team International decided to do research and find out whether mutation of the protein would result in sickle cell disease as well. We hypothesize that if hemoglobin B is conserved within animals, then they can possibly develop sickle cell anemia.

Methods and Results

We first looked up HBB2 on Entrez Gene in order to retrieve the sequence for HBB2. Following the retrieval of the sequence, we then went to BLAST and ran it, coming up with a near perfect match to a cloned protein taken from a Sumatran Orangutan’s blood sample. We also found high-matching fragments that were anywhere from 11-50% query coverage. Although most fragments were from Homo sapiens, there were quite a few from other primate species, such as Common Chimpanzees.

Methods and Results With the help of BLAST, we were able to retrieve HBB2-

similar sequences from other animals, which are listed below:

Common Chimpanzee(Pan troglodytes) Sumatran Orangutan (Pongo abelii) Rhesus Macaque (Macaca mulatta) Olive Baboon (Papio anubis) Common Marmoset (Callithrix jacchus) Tufted Capuchin (Cebus apella) Common Squirrel Monkey (Saimiri sciureus) Nancy Ma's Night Monkey (Aotus nancymaae)

Methods and Results We decided to use those sequences because fully half of

them come from Old World Primates(the first 4 species) and the other half come from New World Primates. We thought it would be interesting to see whether the Old World or New World Primates would have HBB2 sequences similar to humans. We also used Equus caballus(Horse) as an outgroup.

Following the retrieval of the FastA sequences, we went ahead and did the PHILYP protocol using Muscle, and generated the following Phylogenetic trees.

Methods and Results

+------HBB2-Night +-31.4-| +-87.4-| +------HBB2-Squir | | +---------100.0-| +--------------HBB2-Capuc | | | +----------------------HBB2-Marmo | +-100.0-| +--------------HBB2-Orang | | +-78.5-| | | | | +------HBB2-Human | | +-29.5-| +-84.8-| | | | | +------HBB2-Chimp | +-90.2-| | | | +----------------------HBB2-Rhesu | | | +------------------------------HBB2-Baboo | +----------------------------------------------HBB2-Horse

Figure 1: Phylogenetic Tree #1, showing the relationships between the hemoglobin from different primates.

Methods and Results

+--------------HBB2-Capuc +-56.0-| | | +------HBB2-Squir +--------100.0-| +-41.0-| | | +------HBB2-Night | | | +----------------------HBB2-Marmo | +------| +--------------HBB2-Orang | | +-79.0-| | | | | +------HBB2-Chimp | | +-50.0-| +-88.0-| | | | | +------HBB2-Human | +-75.0-| | | | +----------------------HBB2-Rhesu | | | +------------------------------HBB2-Baboo | +----------------------------------------------HBB2-Horse

Figure 2: Phylogenetic Tree #2, showing the relationships between the hemoglobin from different primates.

Methods and Results

From those trees, we found that the closest HBB2 relatives to humans are orangutans and chimpanzees, so we did a literature search on PubMed for “sickle cell anemia chimpanzees” and “sickle cell anemia orangutans”. The first search term came up with two articles pertaining to sickle cell anemia, but neither had anything pertaining to chimpanzees naturally contracting sickle cell anemia. The second phrase did not come up with any articles.

We then expanded our search to include the Google Scholar database and to include all primates, but still no relevant articles were found.

Discussion

In this project we tried to examine the HBB2 gene to see whether all the species having this gene are susceptible to contain the Sickle Cell Anemia mutation. At first we started searching for the species having this gene which are Common Chimpanzee (Pan troglodytes), Sumatran Orangutan (Pongo abelii), Rhesus Macaque (Macaca mulatta), Olive Baboon (Papio anubis), Common Marmoset (Callithrix jacchus), Tufted Capuchin (Cebus apella), Common Squirrel Monkey (Saimiri sciureus), and Nancy Ma's Night Monkey (Aotus nancymaae).

Discussion

In order to find out this we selected two main species which are closely related to Homo sapiens they are Common Chimpanzee (Pan troglodytes), Sumatran Orangutan (Pongo abelii). We tried searching for any literature pertaining to these animals naturally acquiring Sickle Cell, but no relevant studies appeared, not even for any primate.

Conclusion

We tried to explore the properties and functionality of hbb2 in some primate species, like chimpanzees, orangutans, macaques, baboons, and squirrel monkeys, as these are found to have the gene sequences similar to that of human species. We came to know these similarities from the phylogenetic trees which were retrieved using Philyp through MUSCLE.

Conclusion

As part of our work, we compared New World and Old World Primates to see if either of them would have HBB2 sequences similar to humans. Among all these species chimpanzees and orangutans were closely related.

Conclusion

So, we started exploring the HBB2 sequences in similarly related animals using PubMed and Google scholar databases but could only retrieve limited results for chimpanzees being artificially injected with blood from a sickle-cell patient.

Conclusion

From what we found, we do not think that animals other than humans can naturally acquire Sickle Cell Anemia, in contrary to our hypothesis. Further research may, however, see whether primates other than humans can acquire sickle cell anemia, by examining their hemoglobin genes and seeing whether it is genetically possible for primates to acquire Sickle Cell Anemia.

Works Cited Remington, N., Stevens, R.D., Wells, R.S., Hohn, A., Dhungana, S., Taboy,

C.H., Crumbliss, A.L., Henkens, R., and Bonaventura, C. 2008. Genetic Diversity of Coastal Bottlenose Dolphins Revealed by Structurally and Functionally Diverse Hemoglobins. PubMed Central. Retrieved from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2242852/?report=abstract&tool=pmcentrez

Shechter, A.N. 2008. Hemoglobin Research and The Origins of Molecular Medicine. The American Society of Hematology. Retrieved from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2581994/?tool=pmcentrez

Browning, J.A., Staines, H.M., Robinson, H.C., Powell, T., Elory, J.C., and Gibson, J.S. 2006. The Effect Of Deeoxygenation On Whole-cell Conductance Of Red Blood Cells From Healthy Individuals and Patients With Sickle Cell Disease. Blood. Retrieved from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2951509/?tool=pmcentrez

Sara Gardenghi,1 Pedro Ramos,1,2 Maria Franca Marongiu,1 Luca Melchiori,1 Laura Breda,1 J Clin Invest. 2010 December 1; 120(12): 4466–4477.