Topic 10 - Next Generation Sequencing Flashcards
what is NGS and what is another name commonly used for it
next generation sequencing
massively parallel DNA sequencing
what is next generation sequencing
a DNA sequencing technology that can manage many DNA sequences at once
looks at many STR regions, at the length of the fragments and the DNA sequence of each fragment also
has very high sensitivity
what 3 types of sample is NGS good for
small amount
aged
compromised
who is the NDNAD run by
the home office
what two factors influence the decision of what SNP sequencing method to use
the quality and quantity of the DNA
what was the first NGS instrument developed and validated for use in forensic genomics
using this, how many STR markers could be analysed in a single test
the MiSeq FGx Sequencing System - ISO 17025 accredited
230 markers in approx 48 hours
what are the three options of SNP sequencing to choose from (briefly explain each)
- SNP microarray = 600,000 SNPs, 200ng sample, least expensive, not good for degraded
- Targeted Kit- Kintelligence = 10,000 SNPs, >50pg, mid range cost. use in labs
- whole genome sequencing = 1 million SNPs, >50pg, expensive, good for degraded DNA
what is a microvariant allele
an allele with an incomplete or incorrect repeat unit
can complicate NGS
what are the benefits of NGS (8)
- 200 markers can be looked at simultaneously
- access wider range of informative markers
- good for challenging samples
- highly discriminating data
- fast
- can do 96 samples at once
- gives more info than current multiplex systems
- can be used for Forensic DNA phenotyping e.g eye colour, hair colour
what is the next steps to use NGS for
estimation of
- age
- skin colour
- ancestry
what could NGC be coupled with to help massively in investigations
forensic investigative genealogy
when is NGS most suitable
for heavily degraded samples
it is expensive so if we can use other methods such as DNA 17 then why not
