28-03-2011, 02:18 PM
presented by:
Raphael Anstey
Matthieu Chardon
Travis Harper
dnachip-091026143639-phpapp01.ppt (Size: 1.78 MB / Downloads: 209)
What is a DNA Chip?
• Micro-Array containing all the genes (roughly 40,000) in the entire Human Genome (complete Genetic Code).
• Each known gene or “probe” occupies a particular “spot” on the chip, and varying levels of fluorescent activity show varying levels of gene activity in introduced genetic material.
• By introducing these samples or “targets” we can determine which genes are most active for traits, immunities, or any hereditary condition including disease.
The Power of Micro-Arrays
• Micro-Arrays quickly show the relationships between specific genes and specific traits, diseases and the like.
• Thus, we efficiently gain valuable insight into how our genetics specifically affect us.
Background on DNA
To truly understand Deoxy-RiboNucleic Acid(DNA) chips, we must first understand the elegance and complexity of DNA and genetics
Historical Introduction
• Genetics started in 1866 when a monk named Gregor Mendel discovered biological elements called genes that were responsible the possession and hereditary transfer of a single characteristic.
• Genes were linked to DNA, but it took James Watson and Francis Crick deduced the double helix structure of DNA in 1953.
• Most recently, the joint venture of the Human Genome Project and a company called Celera published the first draft of the human genome in February 2001.
Genes and mRNA in Protein Production
• A gene is a region of DNA that controls a discrete hereditary characteristic, usually corresponding to a single mRNA that carries the information needed for constructing a protein. Amazingly only 3% of DNA contains genes, the rest is inactive.
• “Messenger” Ribonucleic Acid(mRNA) copies the genetic material off of a DNA strand and transports it form the nucleus to the cytoplasm where Amino Acids are grown into proteins.
Applying DNA Principles to Chips
• Chips are designed to either “sequence” or decode genetic strands, or to find genetic matches.
• HYBRIDIZATION
• The array provides a medium for matching known and unknown DNA samples based on base-pairing (hybridization) rules. The two strands basically combine automatically if correct matching has occurred.
The Human Genome
• Intended to produce a DNA sequence representing the functional blueprint and evolutionary history of the human species
• Identify all of the approximately 30,000 genes in human DNA
• Determine sequences of 3 billion chemical base pairs that make up DNA
• Expensive arduous process - Eleven years, three billion dollars
• Applications in diverse biological fields:
o molecular medicine
o microbial genomics
o bioarcheology
o DNA identification
o bioprocessing
Functional Genomics
• Thousands of genes and their products in a given living organism function in a complicated and orchestrated way that creates the mystery of life
• Whole picture of gene function is hard to obtain in varying one gene per experiment
• Simultaneously analyzing expression levels of a large number of genes provides the opportunity to study the activity of an entire genome
• The DNA Chip permits these kinds of analyses