DNA PROBES Flashcards
What is a dna probe
a short single stranded length of dna that has some sort of label attached
what labels are attached
radioactive or fluorescent
describe the radioactive labelled probe
it is made up of nucleotides with 32 phosphate
describe the fluorescently labelled probe
they emit light flourescnece when bound to target dna sequence
how are the desired genes located
using genetic libraries that have most of the base sequence for most genetic disease
what is produced
a fragment of dna with the complimentary base pairings to the gene we are trying to locate
what is then done to this dna
it is replicated by the pcr and labelled
what is then done to the suspect dna
they are heated to separate the two strands
what happens when the mixure cools
hybridisation it is likely that the dna probe with complimentary fragment will bind to the complimentary target dna
what is then done to the sample and why
it is washed to remove any unattached dna probes
then what can we see
the hybridised DNA that contains that mutant allele gene code
