Gene Technology Flashcards
Enzyme which can manufacture DNA from RNA
Reverse transcriptase
Eg HIV, a virus containing RNA as genetic material which can replicate by manufacturing complementary DNA.
Eg HIV, a virus containing RNA as genetic material which can replicate by manufacturing complementary DNA.
Processes by which genes are manipulated, altered or transferred from organism to organism.
Recombinant DNA Technology (genetic engineering)
DNA of two different organisms combined as a result of gene transfer
Recombinant DNA
Promoter
Region of DNA required to allow transcription of the gene to take place.
Terminator
Region of DNA required to stop transcription at the appropriate point
An enzyme which manufactures DNA by joining nucleotides (using a complementary strand as a blueprint).
NB it does NOT cause complementary base pairing
An enzyme which manufactures DNA by joining nucleotides (using a complementary strand as a blueprint).
NB it does NOT cause complementary base pairing
An enzyme which recognises and cuts DNA at a specific sequence of bases
Restriction endonuclease
Gene machine
A method of producing a gene by feeding the desired nucleotide sequence into a computer.
Short sequence of DNA
Oligonucleotide
An organism resulting from gene transfer from one organism to another, which has recombinant DNA
Genetically modified organism (GMO)
A carrier eg a plasmid or virus
Vector
Isolation of DNA; insertion into vector; transformation into host; identification by gene markers; growth/cloning of host cell population
Gene transfer/cloning stages
Complementary DNA
cDNA made with nucleotides lined up which are complementary to the mRNA template strand
Palindromic sequence
nucleic acid sequence on double-stranded DNA or RNA where reading the 5’ to 3’ forward on one strand matches the sequence reading backward 5’ to 3’ on the complementary strand
The sequence of nucleotides exposed following an oblique ‘cut’ by a restriction endonuclease
Sticky ends
DNA ligase
An enzyme which can join the phosphate-sugar framework of two sections of DNA eg joining sticky ends
Transformation
Reintroduction of plasmids back into host bacterial cells, by mixing them in a medium containing Calcium ions to increase their permeability
Ways to identify whether a gene has been taken up by a bacterial cell eg using antibiotic resistance, fluorescence or specific enzyme presence.
Marker genes
Replica plating
Method to identify bacterial cells with plasmids carrying antibiotic resistance genes by plating on antibiotic-rich medium
Automated method of in vitro cloning in which fragments of DNA are copied very quickly and many billions of times
Polymerase chain reaction
A short sequence of nucleotides with a set of bases complementary to those at one end of each of the two DNA fragments
Primer
Annealing
Joining of the primers to their complementary bases at the end of the DNA fragment
A computer-controlled machine that varies temperatures precisely over a period of time
Thermocycler
Genetically modified crops changed by insertion of gene eg for resistance, over-fast softening of fruit
GM crops
Trade name for world’s first anticoagulant to be made from a genetically modified animal (a goat via its milk)
(Atryn) Anti-thrombin
Using defective gene replacement using genes cloned from healthy individuals
Gene therapy
Therapy involving replacing or supplementing the defective gene in the fertilized egg, so all of the cells in the new organism develop normally. Currently prohibited.
Germ-line gene therapy
Therapy involving targeting the damaged tissue itself, so needs to be repeated periodically as cells die and need replacement.
Somatic-line gene therapy
CFTR
Cystic fibrosis trans-membrane-conductance regulator – chloride ion channel protein controls transport of Chloride ions across epithelial membranes.
Viruses which infect the respiratory tract, by injecting their DNA into epithelial cells of the lungs, so are useful vectors for gene transfer
adenovirus
Defective gene is replaced with a healthy gene
Gene replacement
Gene supplementation
One or more copies of the healthy gene (which are dominant alleles) are added alongside the defective gene, so the effect of the defective gene is masked
A lipid molecule wrapped around a gene, used to allow it across the cell-surface membrane
liposome
SCID
Severe Combined Immunodeficiency- an example of a genetic disorder which can be helped using gene therapy
The enzyme which destroys toxins which would otherwise kills leucocytes (white blood cells). The ADA gene is one which has been treated using gene therapy
Adenosine deaminase
DNA probe
Short, single stranded length of DNA linked to an easily identifiable label eg radioactive or fluorescent probes
Combination of separated DNA strands with the probe, by binding it to the complementary bases on one of the strands.
DNA hybridisation
Methods to determine the exact sequence in which the nucleotides are lined up in a piece of DNA eg Sanger sequencing
DNA sequencing
Method to separate the radioactively-labelled fragments of DNA after PCR by applying a voltage across a gel matrix, followed by detection using photographic film
Gel electrophoresis
Cutting DNA with a series of different restriction endonucleases (eg HindIII, BamHI, NotI), then separating the fragments. Distance between recognition sites can be discovered by the patterns of fragments produced.
Restriction mapping
Checking for individuals in a family for a mutant allele eg sickle-cell anaemia
Genetic screening
Genetic counselling
Advice for people at risk of genetic conditions i.e. when in family history, to discover risk to them and their family of its inheritance
Genetic fingerprinting
(genetic profiling)
Technique to determine the genetic identity of an organism eg in forensics, paternity cases, diagnostics, breeding programmes in conservation. It depends on an organism’s genome containing repetitive, non-coding introns, which have core sequences unique to the individual.
