Genetic modification and biotechnology

Nature of science:

Assessing risks associated with scientific research—scientists attempt to assess the risks associated with genetically modified crops or livestock. (4.8)

• Gel electrophoresis is used to separate proteins or fragments of DNA according to size.
• PCR can be used to amplify small amounts of DNA.
• DNA profiling involves comparison of DNA.
• Genetic modification is carried out by gene transfer between species.
• Clones are groups of genetically identical organisms, derived from a single original parent cell.
• Many plant species and some animal species have natural methods of cloning.
• Animals can be cloned at the embryo stage by breaking up the embryo into more than one group of cells.
• Methods have been developed for cloning adult animals using differentiated cells.

Applications and skills:

• Application: Use of DNA profiling in paternity and forensic investigations.
• Application: Gene transfer to bacteria using plasmids makes use of restriction endonucleases and DNA ligase.
• Application: Assessment of the potential risks and benefits associated with genetic modification of crops.
• Application: Production of cloned embryos produced by somatic-cell nuclear transfer.
• Skill: Design of an experiment to assess one factor affecting the rooting of stem-cuttings.
• Skill: Analysis of examples of DNA profiles.
• Skill: Analysis of data on risks to monarch butterflies of Bt crops.

• The use of DNA for securing convictions in legal cases is well established, yet even universally accepted theories are overturned in the light of new evidence in science. What criteria are necessary for assessing the reliability of evidence?

Utilization:

• Syllabus and cross-curricular links:
• Biology
• Topic 2.7 DNA replication, transcription and translation

Aims:

• Aim 6: The design of a rooting experiment should ideally lead to the experiment actually being carried out by students.
• Aim 8: The ethics of genetic modification could be discussed.

• Students should be able to deduce whether or not a man could be the father of a child from the pattern of bands on a DNA profile.
• Dolly can be used as an example of somatic-cell transfer.
• A plant species should be chosen for rooting experiments that forms roots readily in water or a solid medium.