Week 12 Flashcards
Southern blotting
DNA digested on gel –> transferred to membrane –> probed
RFP for disease diagnostics
Identify diseases within family passed from 1 gen to the next.
Allele-specific oligonucleotide as probes for disease diagnostics
Digest –> run on agarose gel –> transport to membrane –> analyse nucleotide
PCR diagnostics for disease diagnostics
Different size of bands if hetero/homozygous or none.
Can see deletions and repeats.
If stained, can see results immediately.
DNA profiling
Use Variable number of tandem repeats (VNTRs) and short tandem repeats (STRs).
Mitochondrial SNPs advantages
High copy number
Most common genetic variant
Mitochondrial SNPs disadvantages
Less alleles in population
Cannot identify mixed DNA
Can differentiate only small sample pool
All siblings have the same as the mother.
What is 16S rRNA
Essential sequence in bacteria.
Level of sequence identity correlates to degree of relatedness and can distinguish closely related.
How is 16S rRNA used for identifying bacterial strands?
Amplify 16S rRNA from sample –> gel purify and amplify –> sequence –> repeat and search database
Arbitrarily primed PCR for strain identification
Low to high stringency
High accuracy within laboratory only
Multilocus sequence typing
Look at housekeeping genes (small and easy to sequence areas) and look at polymorphic sites.
Repeatable between laboratories and requires no culture.
How is antimicrobial susceptibility testing
Disk with antibody –> diffuses out of disc into agar –> if not resistance, bacteria cannot grow.
Resistance gene detection by PCR - why?
Pop may be slow growing
Resistance by different mechanisms
Resistance highly conserved (horizontal transference)
Genetic DRIFT evolution of disease happens how?
Progressive accumulation due to low fidelity of RNA polymerase. Pop has some level of immunity
Genetic SHIFT evolution of disease happens how?
Sudden, when virus enters human and infects same cell as another they share RNA and rapidly mutate. Pop has no immunity
