Genomic sequencing Flashcards
genomic sequencing can be used in
- personalised medicine
- genetic disease
- clinical diagnosis
history of genetic sequencing can be broken down to three stages
first-generation
second-generation (NGS)
third- generation
the first generation included the invention of the
chain termination technique
the chain termination technique is now called
Sanger sequencing
sagger sequencing provide high quality reads of up to
1 kb
sanger sequencing is still often regarded as
the gold standard for DNA sequencing
sanger sequencing benefits
high fidelity- therefore used to validate NGS data
sanger disadvantages
low-throughput
difference between first-generation and second-generation seuqnecing
- consierdably shorter reads (a few hundred)
- massively higher throughput
throughput in second gen
billions of reads per run
second gen name
NGS
Names of NGS sequencing systems (2)
IlluminaMySeq
SOLiD system
name 3 different sequencing techniques for NGS
pyrosequencing
Sequencing by synthesis
Sequencing by ligation
short read platforms allow scientists to
quickly hunt for causative mutations in a panel of disease genes- the exome or even the entire human genome
short read lengths can
introduce gaps and ambitious regions in de novo assmebly
third generation is characterised as
single molecule sequencing
third generation does not use
PCR- therefore lacks amplification biases
name two third generation sequencing technologies
single molecule real-time (SMRT) and Pacific Biosciences (PacBio)
advantage of third generation sequencing
exceptionally long read lengths
can detect epigenetic modifications
only last several hours
low-cost
