21.4 Locating genes, genetic screening and counselling Flashcards
1
Q
Why is it important to know where a gene is located
A
Recombinant DNA technology allows us to treat many genetic disorders, which tend to carry disease.
In order to do this we need to know where the gene is located
2
Q
What is a DNA probe
A
Short single stranded length of DNA that has a label attached so can be easily identified
3
Q
What are the two most commonly used probes
Radioactive
Fluorescent
A
. Radioactively labelled probes are made of nucleotide with isotope 32P.
The probe is identified using an x-ray film that is exposed by radioactivity
. Fluorescently labelled probes emit light under certain conditions
Eg when probe has bonded to target DNA sequence
4
Q
How can DNA probes identify particular alleles of genes
A
- DNA probe is made of a particular base sequence that is complimentary to part of base sequence on DNA
