Medical Interventions Mrs. Stewart Central Magnet School

1. No student should copy data from anyone who is not his or her lab partner. 2. You may discuss the experiment with your lab partner and other classmates, but the lab report that you turn in must be your own work. Lab reports are subject to all the rules governing academic honesty. 3. Photocopies of any parts of the lab report are not permissible.

 Role – scientist  Audience – scientific community  Format – formal lab report  Topic – DNA microarray experiment

 What was the purpose of this lab?  Comparing healthy non-smoker’s lung cells to Grandpa’s (heavy smoker) lung cells to determine the differences in the gene expression of 6 genes of interest

 Why did we perform this study (experiment)?  If I didn’t know what a DNA microarray does, how could you explain that to me?  Which genes are we studying in this lab? (list and give details about what each gene codes for)  Why are we interested in these genes?  End with a specific problem that we are examining.  Do NOT tell me anything about this class and what we have done in here!!!!

 Independent variable(s)  Non-smoker lung cells and smoker lung cells  Dependent variable(s)  The gene expression ratios

 Predictions- what you expect the results of the lab to be  Example: We expect to see more activity in the smoker’s lung cells for genes 1 and 5, less activity in the smoker’s lung cells for genes 3 and 6, equal activity for gene 2 in both cells and no activity in either cell for gene 4.  Hypothesis – formal way to write the prediction  In this lab, it is expected that genes 1 and 5 will be found induced in the smoker’s lung cells, genes 3 and 6 will be found suppressed in the smoker’s lung cells, gene 2 will show equal activity in both non-smoker and smoker’s lung cells and gene 4 will show no activity in either cell.

 Level of detail is an art form!  Ask: what details have an influence over my results?  These are the essential details  Do NOT list the materials as a separate list

 Goggle and gloves must be worn for this experiment. Obtain 6 different gene solutions with prepared DNA strands and agar to solidify on a slide. Melt the 6 different gene solutions in a water bath at 70 degrees Celsius. Obtain a microarray slide with at least 6 labeled locations for DNA to be fixed. Once gene solutions are completely melted, place one drop onto the correspondingly labeled location on the slide. Allow one minute for gene solutions to solidify on slide. Obtain a prepared hybridization buffer solution, that contains cDNA from both healthy lung cells and cDNA from smoker’s lung cells. Place one drop from hybridization buffer onto each of the 6 gene locations on the slide. Ensure that the tip of the bottle does not touch the gene solution to prevent cross contamination. Wait one minute, then compare the colors observed to color chart to determine gene expression ratios.

 Includes figures and text to explain the figures only.  DO NOT discuss what the results mean or indicate here. Gene expressionColor Induced (has greater activity levels) in smoker’s lung cells Pink Suppressed (has less activity) in smoker’s lung cells Blue Expression levels are the same in both non-smokers and smoker’s lung cells Purple Not expressed in either non-smokers or smoker’s lung cells Clear (colorless)

GenePredicted result Actual results - color Gene Expression ratios observed 1Induced – Pink ~ 6 2Equal in both – purple 1 3Suppressed – blue.25 4Neither – clear 0 5Induced – pink 3 6Suppressed - blue.5

 This is where you interpret your results – tell the reader what the results may indicate  How do your results compare to what you predicted?  How might you explain any unexpected results?  What are some possible sources of error to explain why your results may have differed from your predictions?  How could you improve this experiment if you were to repeat it?

 Final statement to summarize lab results.  Examples:  The increased activity in genes 1 and 5 and the decreased activity in genes 3 and 6 may lead to cancer in smoker’s.  Or  Due to the errors in the experiment, it should be corrected and performed again before conclusive results can be obtained.

 Lab report summarized in a paragraph  Introduction: the main focus of the lab (scientific concept or lab procedure the lab is about) and the main objective(s) of the lab  Methods: a quick description of how the lab was done  Results: statement of the overall findings  Discussion: statement explaining the findings of the lab and their relationship to the scientific concept or lab procedure  Conclusion: what you learned about the scientific concept or lab procedure

 A few words that describe the experiment  Catchy titles are good, but does it describe the experiment??  Must capture main point of the lab.  Examples:  Good: enzyme activity in neurons of patients with alzheimers  Bad: enzymes  Bad: enzymes in alzheimers

Clear, concise title goes here! Your Name Your lab partner(s) Medical Interventions Activity # Date of lab