exploring precision medicine

Exploring Precision Medicine

What is precision medicine?• An emerging approach for disease treatment and prevention that

takes into account individual variability in genes, environment, and lifestyle for each person

• Allow doctors and researchers to predict more accurately which treatment and prevention strategies for a particular disease will work in which groups of people.

• The “one size fits all” approach the medicine is not always effective

Cancer Treatment

Learning Outcomes

• Describe the relationship between SNPs and gene expression

• Explain how the gene TAS2R38 impacts taster phenotype

• Model the process of PCR and explain its components

• Provide examples of how DNA sequencing may impact medicine in the future

• Recognize the connection between genetics and drug metabolism

Medicine: A Complex Puzzle

• Asthma is a very common condition that affects the respiratory system and makes it extremely difficult for a patient to breathe

• Researchers believe asthma has a strong genetic component that can be further exacerbated by environmental conditions

Storyline Overview

• Medications Are Not One-Size-Fits-All

• DNA, SNPs and Drugs

• Personalization: The Future of Medicine?

• TAS2R38: A Vehicle for Understanding the Genotype-Phenotype Relationship

DNA Extraction - Chelex Resin

• Produced by Bio-Rad, 500 g = $856

• Binds to metal ions, including Mg2+ (magnesium ions)

• DNAase enzymes degrade DNA in the cytoplasm• need to Mg2+ function

Amplifying PTC DNA by Polymerase Chain Reaction (PCR)

1. PCR Master Mix (22.5 uL) and DNA (2.5 uL) in PCR tube

• Gene specific primers – locate the PTC gene

• dNTPs (mixture of A T C G nucleotides)

• Salts – neutralize the electrically charged sugar phosphate backbone

• pH of 8.9

• One Taq DNA Polymerase

2. Perform PCR Amplification using miniPCR Thermocycler

PTC Gene• Ability to taste PTC (phenylthiocarbamide) is an inherited dominant trait

• Varies in the human population and influences taste

• PTC taste receptor gene is TAS2R38 (located on chromosome 7) – bitter tasting ability

• PTC gene is just one of 30 bitter taste receptors on the tongue

Single Nucleotide Polymorphism (SNP)

• SNPs are common genetic variations

• A SNP represents a variation in a single nucleotide of a gene

• Use HaeIII restriction enzyme to recognize the SNP sequence of the PTC gene

GGCC

Single Nucleotide Polymorphism (SNP)

• Identify subtle differences in DNA and how they affect you

Amplifying PTC DNA by Polymerase Chain Reaction (PCR)

Another Dramatic PCR Animation