The VTeen 4-H Science Pathways Café was thrilled to invite Dr. Debra Leonard, the chair of the University of Vermont Pathology Department, to speak about genes on March 30. We were extremely grateful that Dr. Leonard was able to take some time out of her busy schedule to teach us about how genomics and genetics are used to diagnose and treat diseases.
Dr. Leonard began with the basics of genetics and genomics: the structure and function of DNA, how it is arranged into chromosomes and genes, and how genes express themselves in genotype and phenotype. It was a helpful review for kids who had studied biology and a useful introduction for those who hadn’t. Most importantly, we learned how DNA replicates, how it is transcribed to form amino acids which make up proteins, and how mutations occur. Small errors in nucleotide bases may cause diseases such as sickle cell anemia or cystic fibrosis. Additionally, since half of an offspring’s genetic material comes from each parent, a person may have zero, one, or two instances of a mutated or undesirable gene. This means some traits have “carrier” states in which the carrier does not have the disease but has one copy of the affected gene that can be passed on. All of these complicated factors go into genomics, the study of the complete set of human genes (or genome).
Hands on Activity
Next, we put what we had learned into action. Dr. Leonard had prepared two case studies for us to investigate using the Internet. The first was a real-life scenario involving her husband, who was an avid runner. When he got his genome sequenced, he learned that he had a mutation with the code Met694Val on the MEFV gene, meaning that the amino acid methionine was replaced with the amino acid valine at protein position 694. Our task was to figure out how this mutation affected Dr. Leonard’s husband. Through research, we found that the MEFV gene instructs the body to produce pyrin, a protein that helps with controlling inflammation. The mutation causes this protein to be produced incorrectly, leading to a disease known as familial Mediterranean fever (FMF). This made sense, as Dr. Leonard’s husband would require an abnormally long recovery time whenever he was injured. FMF can be treated with anti-inflammatory drugs.
The next case study was about a man whose grandmother had died from frontotemporal dementia and wanted to know if he or his children were at risk. His sequenced genome had a mutation on the MAPT gene. We discovered that the MAPT gene directs the body to produce tau proteins, which stabilize microtubules in neurons. With the mutations, the tau proteins are ineffective and the microtubules collapse, causing the deterioration of mental function. The man in the case study was at risk of getting frontotemporal dementia himself and passing it to his kids. Currently, frontotemporal dementia has no cure, so this would’ve been grim news for this man. This led to a discussion about why someone might want to know about their risk of inheriting a fatal disease. There are numerous factors, including financial and family planning, emotional closure, and starting treatment as early as possible.
To conclude, Dr. Leonard reiterated the importance of the work she does. The study of the human genome is one of the newest and most exciting fields in science, with the power to diagnose and treat diseases. New discoveries within the field are constantly being made, and it is constantly becoming easier and cheaper to sequence a human genome. We were incredibly honored to have Dr. Leonard speak about a topic she is passionate about and inspire the next generation of genetic counselors and researchers.
Learn more about the University of Vermont, Larner College of Medicine, Department of Pathology and Laboratory Medicine at http://www.med.uvm.edu/pathology/aboutus/about