Biology 3594A Study Guide - Final Guide: Comparative Genomic Hybridization, Snp Genotyping, In Silico
13 May 2018
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Lecture 11 Flashcards
Front (Term)
Back (Definition)
Mutator phenotype: phenotype and
genotype
Observed phenotype is too many mutations
Genotype
- heritable change in DNA repair genes
- could be aberrant DNA repair
- Hypothesis of a mutator phenotype developed to explain
disconnect between the rarity of spontaneous mutations but
the high level of mutations observed in tumours
Hybridization
Get a piece of DNA to form acomplementary match with
target, H-bonds betweennucleotides
- wantprobes to bind but then you want only the specific
matches to remain and washeverything else off
DNA complementarity and Hydrogen
bonding - high stringency conditions
- low stringency conditions
High stringency conditions
- high temp
- low salt
Low stringency conditions
- low temp
- high salt
How to capitalize on DNA
complementarity and H bonding
(CGH, SNP, Southern, FISH)
Start with low stringency
- probes will hybridize to template
Then raise stringency
- non-specific sequences will wash off and leave behind your
perfect match
- increase stringency to achieve specificity
Don't go so high that everything comes off the sample (can
determine melting temp)
- could still get false positives, need to validate
In situ vs in silico
(Comparative genomic hybridization)
In situ - do with a karyotype of chromsomes
In silico - platform with probes
Comparative Genomic Hybridization
- low vs high resolution
Increased resolution = probes that represent more of the
genome, maybe every 1000 nt you make a probe
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Hypothesis of a mutator phenotype developed to explain disconnect between the rarity of spontaneous mutations but the high level of mutations observed in tumours. Get a piece of dna to form acomplementary match with target, h-bonds betweennucleotides. Wantprobes to bind but then you want only the specific matches to remain and washeverything else off. Dna complementarity and hydrogen bonding - high stringency conditions. Non-specific sequences will wash off and leave behind your perfect match. Don"t go so high that everything comes off the sample (can determine melting temp) Could still get false positives, need to validate. In situ - do with a karyotype of chromsomes. Increased resolution = probes that represent more of the genome, maybe every 1000 nt you make a probe. How to capitalize on dna complementarity and h bonding (cgh, snp, southern, fish) In situ vs in silico (comparative genomic hybridization) Every 10 000 nt between the loci you probe.
