The analysis of the human genome was first called pointless and a "waste of time" by critics, but as research has been performed and the genome has been collected, we have found many ways of applying our genetic sequences to very significant life scenarios. The human genome has been used to identify disease-causing genes, develop pharmaceuticals for diseases, study evolutionary patterns across species, track generational genetic lineage among humans, identify gene functions, and figure out how the genome works in general. In this lab, we'll use a small-scale simulation of a microarray to test 6 genes that are present in lung cells, and test for differences between these genes in healthy lung cells and cancerous lung cells.
Part 2: Experiment
First we'll get our 2 slides. Each have 8 spots for aqueous solutions, though we'll only use 6, since we're only testing for 6 genes. We'll put 20 microliters of each gene sequence on a corresponding spot-- gene 1 on spot 1, gene 2 on spot 2, etc. Then we'll put 20 microliters of a cDNA solution, made with cDNA from each lung tissue sample, on each spot. After about a minute, we'll observe the spots for our results. Blue dots will represent a gene expressed in only the healthy lung sample, pink dots will represent a gene expressed only in the cancerous lung sample, clear dots will represent that the gene isn't in either, and purple will represent that the gene is represented in both.
Part 3: Discussion
We found that the genes expressed in the lung cancer cells (pink) were C4BPA, SIAT9, and partially ODC1. Genes expressed in the healthy lung cells (blue) were partially ODC1, FGG, and CYP24. ODC1 was expressed in both, so it was normal in both samples; it's possible that it's a gene that synthesizes proteins for the lungs. HBG1 was expressed in neither sample. It codes for hemoglobin, which is in blood, which is not specifically directed or produced in the lungs. C4BPA or SIAT9 may be responsible for the cancer in the lung cells, as they are not present in healthy ones, but are present in the cancerous cells.
Some possible sources of error could have been contamination between specimens, dirty slides, incorrect measurements, or user error in placing genes in correct spots.
