DNA manipulation

• agarose gel: a special type of porous gel used in gel electrophoresis, which allows for DNA to be separated by fragment size
• annealing: the second stage in PCR, in which primers attach to the single-stranded DNA
• bacterial transformation: process in which bacterial cells take up segments of foreign DNA that become part of their genetic make-up
• blunt ends: ends of a DNA fragment with no overhanging bases after being cut by an endonuclease
• complementary DNA (cDNA): a strand of DNA that has complementary bases to the opposite strand and is usually produced through reverse transcription
• CRISPR-Cas9: a tool for precise and targeted genome editing that uses specific RNA sequences to guide an endonuclease, Cas9, to cut DNA at the required positions
• Denaturing: the first stage in PCR, double-stranded DNA is heated and separated into single-stranded DNA
• DNA fingerprinting: technique for identifying DNA from different individuals based on variable numbers of tandem repeats of short DNA segments near the ends of chromosomes
• DNA profiling: technique for identifying DNA from different individuals based on variable regions known as short tandem repeats (STRs) or microsatellites
• DNA sequencing: identification of the order or sequence of bases along a DNA strand
• Electroporation: a technique that uses brief exposure of host cells to an electric field to enable the entry of segments of foreign DNA into the cells
• Endonucleases: enzymes, also known as restriction enzymes, that cut at specific sites within DNA molecules
• ethidium bromide: a dye that binds to DNA and illuminates under UV light
• extension the third stage in PCR, in which the Taq polymerase enzyme synthesises a new strand of DNA by adding free nucleotides
• gel electrophoresis: a technique for sorting a mixture of DNA fragments (and other molecules with a net charge) through an electric field on the basis of different fragment lengths
• genetically modified organisms (GMOs): organisms whose genomes are altered through the use of genetic engineering technology
• genome editing: a process by which changes are made to the nucleic acid sequence of genes; also termed gene editing
• heat shock: a technique to transform bacteria in which cells are suspended in a ice cold solution and then moved into a warm solution to increase plasma membrane fluidity
• hypervariable regions: regions in DNA that are highly polymorphic
• insulin: a hormone that allows for glucose to enter cells, reducing blood glucose levels
• ligase: an enzyme that catalyses the joining of two double-stranded DNA fragments
• origin of replication (ORI): a DNA base sequence in a plasmid in which DNA replication begins
• plasmid: a small circular piece of double-stranded DNA that is able to reproduce independently and may be taken up by cells (usually bacteria) in addition to chromosomal DNA
• polymerase: enzyme involved in synthesising nucleic acids
• polymerase chain reaction: a technique used to amplify a segment of DNA
• pre-proinsulin: an inactive precursor molecule of insulin that includes a signal peptide
• proinsulin: a modified form of pre-proinsulin and the precursor to insulin, in which the signal peptide has been removed and disulfide bridges have formed between chains