Profiling/screening Flashcards
Gene
Unit of inheritance that codes for a protein.
DNA profiling
Cutting Dan into bands/fragments based on size by restriction enzymes and an electric current. Profiling allows DNA to be compared
DNA profiling stages
1.) DNA samples for comparison inserted into wells (holes) within a specially prepared gel containing restriction enzymes that will fragment the DNA.
2.) As electric current is passed through samples they start travelling up the gel, while doing so the samples fragment.
3.)Fragments are separated on size.
4.) Very reliable method.
Genetic Screening
Testing for the presence or absence of a gene; especially important with respect to inheritance and hereditary diseases.
Genetic Engineering
The artificial manipulation of genes between organisms of different species such that they can perform tasks not typically associated with the organism.
Genetic Engineering examples
Micro-organism eg.
Animal eg.
Plants eg.
-Bacteria producing insulin
- Clotting factor VII in sheep
-Weed killer resistant crops, potato blight resistance
Stages & Process of genetic engineering
1.) ISOLATION –> Identifying and isolating the gene in humans, Isolation & cutting of the human gene required carried out by restriction enzymes.
2.) CUTTING –> Making a cut in the DNA of the bacteria to which the isolated gene can be added. All cutting of genes & chromosomes carried out by restriction enzymes.
3.) INSERTION –> Inserting gene into bacterial DNA
4.) LIGATION –> Sealing a gene in place, Enzyme ligase used.
5.) TRANSFORMATION –> Allowing time for gene to be accepted by bacteria (settling in period)
6.) EXPRESSION –> New product (protein) is produced and folded to activate it.
Disadvantages of genetic engineering
- Genetically modified organisms pose a threat to the environment and human health.
- Ethical issues : “designer babies”
