This document discusses DNA barcoding, which is a technique for species identification using short DNA sequences. DNA barcoding uses a standard fragment of the mitochondrial cytochrome c oxidase subunit I (COI) gene to identify species. The technique was formally proposed in 2003 and has since been developed by organizations like the International Barcode of Life project to create a global reference library. DNA barcoding is now used for applications like conservation, pest identification, food safety, and forensics.

1. DNA BARCODING
VEENA P KUMAR
MSC
SCHOOL OF BIOSCIENCES
MGU
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2. WHAT??
• DNA barcoding is a technique in which
species identification is performed by using
DNA sequences from a small fragment of the
genome, with the aim of contributing to a
wide range of ecological and conservation
studies in which traditional taxonomic
identification is not practical.
• Short DNA sequences are called as DNA
barcodes- ranging from 400- 800 bp.
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3. The birth of DNA barcoding
The use of DNA sequences for species
identification has a long history .
But it received significant attention only after it
was formally proposed as ‘‘DNA barcoding’’ in
2003.
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4. • Dr. Paul D.N. Hebert- Father of DNA barcoding
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5. Successful DNA barcode
• Short enough to be quickly sequenced
• Easily identified in all species of organisms.
• Variable enough to provide a unique
sequence for each species
• Size of sequence : 600 – 700 bp
• Universality
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6. Which gene frgments?
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7. Sequencing can be done by a single
organelle region
• Approximately ~650-bp sequences - C-
terminal fragment of the mitochondrial
gene named cytochrome oxidase
subunit I (COI) has been proposed as
universal marker for species level
identification in several animal group.
• Barcodes (mtDNA) have become one of
the most contentious and animated
issues in the application of genetic
information to global biodiversity
assessment and species identification.
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8. Why COI ?
• Mutation rate is fast.
• standard region enough to distinguish closely
related species.
• lack insertions or deletions.
• Greater differences among species Copy
number. (100-10,000 ) .
• Relatively few differences within species.
• Absence of introns.
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9. DNA Barcoding in microbes
1.5 million species of fungi exist, but 10% are
formally described .
Variously used barcode, 400- to 600-bp region of
the nuclear large ribosomal subunit , the internal
transcribed spacer (ITS) gene sequences.
Partial elongation factor 1- (EF-1) sequences
focused on species of Penicillium subgenus
Penicillium (Trichocomaceae, Eurotiales,
Eurotiomycetes, Ascomycota)veena 9

10. DNA barcode for plants
• Compared the performance of 7 leading
candidate plastid DNA regions (atpF–atpH
spacer, matK gene, rbcL gene, rpoB gene,
rpoC1 gene, psbK– psbI spacer, and trnH–psbA
spacer)
• Assessments of recoverability, sequence
quality, and levels of species discrimination,
they recommended the 2-locus combination
of rbcL+matK as the plant barcode.
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11. DNA BARCODING PROCESS
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13. IBOL – International Barcode of Life
• Largest biodiversity genomics initiative
• From 25 nations Scientists are working
together to construct DNA barcode reference
library
• First phase of operations (2010-2015) -
barcode five million specimens representing
500,000 species.
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14. CBOL – Consortium for the
Barcode of Life
• International initiative (2004) .
• To develop DNA barcoding as a global standard for the
identification of biological species .
• 200 Member Organizations from 50 countries .
• ECBOL - EUROPEAN CONSORTIUM FOR THE
BARCODE OF LIFE
• Established as part of the research infrastructure
efforts of EDIT, the European Distributed Institute of
Taxonomy.
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15. CCBD – Canadian centre for DNA
Barcoding
• Largest 'barcode factory', generating hundreds
of thousands of data records per year
• Training barcode researchers from around the
world.
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16. APPLICATIONS
• Protection of Endangered Species ( Conservation)
• Identifying Agricultural pest
• Water quality testing
• Identification of all life stages, eggs, larvae, nymphs,
pupa, adults
• Identification of fragments or products of organisms
• Identification of stomach contents, trace ecological
food-chains
• Food control
• Customs control
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17. • Invasive species control
• Disease vector control
• Agriculture
• Forestry
• Education
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18. THE FUTURE
• Data in seconds to
minutes
• Link to reference
database
• A taxonomic GPS
• Usable by non-
specialists.
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19. THANK YOU…
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