Sickle Cell Anemia Experiment

1959661958 Sickle cell anemia is an inherited disease of the red blood cells. This disease causes blood cells to take the shape of a sickle and cause restricted blood flow through veins, which leads to chronic pain and eventually organ damage. The genetic cause of this blood disorder is a single cell mutation or point mutation in the gene encoding the ß-globin chain of hemoglobin. One adenine nucleotide in normal DNA changes to a thymine nucleotide in patients with sickle cell. The protein affected is hemoglobin, a major protein produced by red blood cells that transports oxygen from the lungs to the tissue. The gene mutation that changes hemoglobin is caused by a single cell mutation in the 6th protein position where adenine in glutamic acid

The change in the amino acid alters the net charge and shape of hemoglobin protein. The guiding question is which individual (X, Y, Z) has sickle cell anemia. The goal is to run DNA tests to see which person has sickle cell anemia.

During the investigation, the group was given six DNA samples, two from each of the three individuals, (Xu, Xc, Yu, Yc, Zu, Zc). Three of the samples were cut and the other three were uncut. Using micropipettes, each person placed 2.5 μ of buffer E and 2 μ of BSA. A restriction enzyme is an enzyme that acts as scissors and cuts double-stranded or single-stranded DNA at a specific recognition nucleotide sequence known as restriction sites. The restriction enzyme used in this lab was Bsu36I. The three members who had

As seen in the graph below, the group observed that sample Xu, Yu, and Zu were 531 base pairs long. Sample Xc was cut into two bands, one being 331 base pairs and the other was 200 base pairs long, this told the group that individual X was normal. Yc remained one strand at 531 base pairs long, this told the group that individual Y has sickle cell anemia. Sample Zc has three strands, one was 531 base pairs long, the second 331 base pairs and the third was 200 base pairs long, this indicated that individual Z was a carrier. The evidence was important because it helped us determine which individual had sickle cell anemia. When restriction enzyme Bsu36I is added to a DNA sample, it cuts the DNA strand at a specific sequence changing it from 531 base pairs to 331 and 200 base pairs. Because of the change in the DNA sequence, Bsu36I is unable to cut the DNA strand. Individual X’s genotype is AA, individual Y’s genotype is SS, and individual Z’s genotype is AS. The group determined the genotypes of the individuals, based on the size and number of bands. If there is one strand the Bsu36UI did not recognize the nucleotide sequence, the person has sickle cell and received two recessive genes from their parents. If there are two strands the Bsu36I recognized the nucleotide sequence and cut the strand, therefore the person is normal. If there are three strands the person is a carrier of sickle cell and received one recessive gene and one normal gene