dna probes and medical diagnosis Flashcards
(17 cards)
What are used to screen individuals for specific alleles?
DNA probes and DNA hybridisation
What is DNA hybridisation?
When a DNA strand from one source binds to a DNA strand from another
What can be used to produce these probes?
PCR
What is the process of making a DNA probe?
A DNA probe is made complimentary to the DNA sequence of the investigated allele
What are these copies made in?
PCR
What is obtained from the person being tested?
DNA samples
What happens to that DNA?
It is fragmented by restriction enzymes
What are these fragments separated in?
Gel electrophoresis
What happens to the fragments then?
They are made to be single stranded
What is used to achieve single-stranded DNA?
Alkaline solution
Where are the single strands transferred to?
Nylon membrane
What is added to the nylon membrane?
DNA probe
What happens to the membrane after adding the DNA probe?
It is washed to remove unattached DNA probes
What will happen if the allele is present?
The labelled DNA will bind to the complementary bases of one of its strands
How is the presence of the probe identified?
The radioactivity or fluorescence
What does it allow patients to be screened for?
Heritable conditions, individual drug responses, health risks
What can it be used in genetic counselling for?
Help people understand the probability of them developing a disease, advise from parents, decide best course of drug treatment for genetic diseases
