Manipulating genomes Flashcards
What is the human genome?
All the genetic material of an organism
What is the genome for eukaryotes?
All the DNA in the nucleus and the mitochondria combined
What is an exon?
The regions of DNA that codes for proteins, only 2% of your total DNA
What is an intron?
Non-coding regions of DNA removed from mRNA before translation
What is satellite DNA?
Short sequences of DNA that are repeated many times, can be microsatellites (smaller sections)
What is DNA profiling?
Producing an image of the patterns in the DNA
The uses of DNA profiling?
Paternity tests, criminal investigations, and identifying individuals at risk of developinga genetic disease
Stages of DNA profiling?
Extraction, digestion, separation, hybridization and development
Explain the extraction stage of DNA profiling?
The Polymerase Chain Reaction (PCR) is used to extract DNA from a tissue sample
The other name for restrictive enzymes?
Restriction endonucleases
Explain digestion stage in DNA profiling?
Strands cut into small fragments using restrictive enzymes, make 2 cuts through each strand of double helix
Explain the separation stage of DNA profiling?
The cut fragments undergo electrophoresis
Explain the process of electrophoresis?
Charged particles move through gel medium under electric current, the gel is immersed in alkali to separate double strands into single strands, transferred onto a membrane by Southern blotting
What is hybridization?
Fluorescent DNA probes added to excess fragments, bind to complementary strands under particular conditions
3 stages of the PCR?
Denaturing, Annealing and Extraction
Which enzyme is used in the extraction of the PCR?
Taq polymerase - can withstand high temps, obtained from a bacteria in hot springs
Examples of where DNA traces can be obtained from?
Hair, blood, semen, saliva and skin cells
Explain what happens at each stage of the PCR?
Denaturing - High temps (90-95) DNA denatures, hydrogen bonds broken, strands separate
Annealing - Temp decrease (55-60) primers bind (anneal) to ends of DNA strands
Extraction - Temp increase (72-75), DNA polymerase builds complementary strands from free nucleotides, Taq polymerase is used
What technique is used for DNA sequencing?
The Sanger sequencing technique
What do the terminator bases do?
Modified fluorescent versions of the four nucleotide bases that stops the DNA synthesis
Explain the Sanger sequence technique?
The DNA is mixed with DNA polymerase, terminator and normal nucleotides, placed in a thermal cycler, DNA adds complementary bases, every time terminator base picked up sequencing stops, sequencing restarts, different length sequences undergo electrophoresis, data fed into a computer
What is bioinformatics?
The development of the software and computing tools needed to organize and analyze biological data
What is computational biology?
Data that is used to build theoretical models of biological systems that can be used to predict different circumstances
