Chapters 19+20: DNA technology and genomes
DNA technology
Techniques: DNA sequencing, gene cloning, PCR amplification, expressing genes,
analyzing gene expression, gene editing
Applications: agriculture, medicine, environmental cleanup, ancestry, forensics
Cloning
1) Desired genes are located in a somatic body cell
2) Nucleus of that cell is removed
3) A donor cell gets the nucleus removed
4) Enucleated egg cell is fused with nucleus from somatic body cell
5) Embryo is produced by mitosis and cell differentiation. It is transplanted into a surrogate
mother. Its develops into a clone of the donor of the genetic material.
Pro’s: produces animals with desirable traits, increases efficiency of breed/livestock
population, offsets losses among endangered species populations
Con’s: decline in genetic diversity, taking nature in our own hands, religious and moral
reasons
Recombinant DNA technique
Gene therapy: treatment of diseases
Manufacture of products (proteins)
Bacteria are often the best organisms: they grow rapidly and cheaply, can be
engineered to produce large amounts of particular protein and often secrete
proteins directly into their own growth medium
Use of the recombinant DNA: joining nucleotide sequences from two different
sources. One source contains the gene that will be cloned. Another source is a gene
carrier (vector)
Technique: cut DNA at specific locations on the DNA (restriction enzymes). DNA
ligase ‘sticky ends’: formation of new recombinant DNA.
Genetically modified organisms (GMO)
Genetically modified: organisms contain one of more genes introduced by artificial
means
Transgenic organisms: contain at least one gene from another species
Pro’s: nutrition rich & cheaper produce, disease resistance
Con’s: possible health risks, impact on local organisms/wild population, religious and
moral reasons
Forensic technologies
DNA profiling: analysis of DNA fragments to determine whether they cone from the
same individual/species. Compares genetic markers from noncoding regions that
show variation between individuals and species. Also paternity testing.
eDNA: identification of rare and elusive species by using fresh or historic samples
The human genome project
Determined the nucleotide sequence of all DNA in the human genome
Identified the location and sequence of all known genes
Identified ‘junk DNA’
Centralized resources for genome sequences
Bioinformatics resources are provided by a number of sources
- National Library of Medicine and National Institutes of Health created the
National Centre for Biotechnology Information (NCBI)
DNA technology
Techniques: DNA sequencing, gene cloning, PCR amplification, expressing genes,
analyzing gene expression, gene editing
Applications: agriculture, medicine, environmental cleanup, ancestry, forensics
Cloning
1) Desired genes are located in a somatic body cell
2) Nucleus of that cell is removed
3) A donor cell gets the nucleus removed
4) Enucleated egg cell is fused with nucleus from somatic body cell
5) Embryo is produced by mitosis and cell differentiation. It is transplanted into a surrogate
mother. Its develops into a clone of the donor of the genetic material.
Pro’s: produces animals with desirable traits, increases efficiency of breed/livestock
population, offsets losses among endangered species populations
Con’s: decline in genetic diversity, taking nature in our own hands, religious and moral
reasons
Recombinant DNA technique
Gene therapy: treatment of diseases
Manufacture of products (proteins)
Bacteria are often the best organisms: they grow rapidly and cheaply, can be
engineered to produce large amounts of particular protein and often secrete
proteins directly into their own growth medium
Use of the recombinant DNA: joining nucleotide sequences from two different
sources. One source contains the gene that will be cloned. Another source is a gene
carrier (vector)
Technique: cut DNA at specific locations on the DNA (restriction enzymes). DNA
ligase ‘sticky ends’: formation of new recombinant DNA.
Genetically modified organisms (GMO)
Genetically modified: organisms contain one of more genes introduced by artificial
means
Transgenic organisms: contain at least one gene from another species
Pro’s: nutrition rich & cheaper produce, disease resistance
Con’s: possible health risks, impact on local organisms/wild population, religious and
moral reasons
Forensic technologies
DNA profiling: analysis of DNA fragments to determine whether they cone from the
same individual/species. Compares genetic markers from noncoding regions that
show variation between individuals and species. Also paternity testing.
eDNA: identification of rare and elusive species by using fresh or historic samples
The human genome project
Determined the nucleotide sequence of all DNA in the human genome
Identified the location and sequence of all known genes
Identified ‘junk DNA’
Centralized resources for genome sequences
Bioinformatics resources are provided by a number of sources
- National Library of Medicine and National Institutes of Health created the
National Centre for Biotechnology Information (NCBI)
