aims to establish a catalogue of all organisms ( 10-30 million species)
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Transcript of aims to establish a catalogue of all organisms ( 10-30 million species)
aims to establish a catalogue of all organisms (10-30 million species)
Ultimately a small portable hand held device will be used to identify samples using information held on a central database.
The project has begun by barcoding fish, plants, birds, and Lepidoptera (butterflies and moths).
Bar Coding
Identifying previously undescribed or cryptic species.
Food chain analysis of gut contents or animal droppings.
Border protection and control:
Identification of agricultural pests and invasive species.
Identification of protected species.
Enforcement of food manufacturing and labeling laws:
Analysis of food product for prohibited ingredients.
Verification of product authenticity.
Analysis of animal feed for prohibited components (e.g animal tissue which may cause BSE).
Hazard analysis (e.g. which bird species is the major contributor to bird strike at airports?).
Bar Code Applications
mitochondrial gene found in all plants and animals.
base sequence is genetically stable because it is inherited from the mother only. It contains no inserted or deleted DNA. This allows for easy genetic comparison.
Mitochondrial DNA
Cytochrome c oxidase subunit 1
Slight different between species.
Allows for unique identification of species.
Intra-species variations generally small (<2%).
CO1 easily recovered from samples.
Fast and inexpensive analysis.
The CO1 gene
Plants, bacterium and some animals. Groups with high intraspecies variability for the CO1 gene
(e.g. amphibians). Groups with <2% sequence diversity for CO1 between
species (variability too low for accurate differentiation plants
Recently diverged species
Hybrid species where the offspring is a result of the mating between a male and female from different species.
Organisms containing nuclear pseudogenes (inactive copies of genes with multiple mutations and/or deletions).
CO1 gene cannot be used for:
Laboratory analysis:
DNA extraction
Amplification (PCR)
Clean up
Sequencing
Specimen collection Bar Coding
Database inclusion:
Barcode of life database (BOLD)
International nucleotide sequence database collaborative
Data analysis:
Specimens identified by finding the closest matching reference record in the database.
Advantages CO1 Cannot be used for
Fastintraspecies variation is too high / interspecies diversity too low
Cheap ($2/sample) recently diverged species
Small samples hybrid species
All life stages (e.g. egg, larvae and adult)
species with nuclear pseudogenes