16.6 locating and sequencing genes

Question	Answer
what is used to locate specific genes?	DNA Probes and DNA hybridisation
what is a DNA Probe?	a short, single stranded section of DNA with some form of label to identify it easily
what are the two most common probes?	radioactively labelled probes fluorescently labelled probes
what is a radioactive probe made up of?	nucleotides with the isotope 32P
how is it identified?	using a photographic plate that is exposed by radioactivity
how do you detect a fluorescent probe?	it emits light under certain conditions
how are they used?	- probe has complementary bases to sequence of wanted gene, - DNA separated into two strands - separated DNA strands mixed with probe, binds to complementary bases -site of binding can be identified by marker
what is it called when the DNA binds with the Probe?	DNA Hybridisation
what needs to be done before making the probe?	find the sequence of DNA of the gene you want to locate
what method is used?	the sanger method
how many test tubes are set up in this method?	4
what goes in each one?	- single strands of DNA to be sequenced, acts as template for synthesis of complementary strand

Resource summary

	Created by Charlotte Hewson about 8 years ago