Manipulating Genomes Flashcards
what is DNA sequencing
identifying the base sequence of a DNA fragment
how have sequencing methods changed over time
used to be manual but has become automated
entire genomes can now be read
give some benefit of genome wide comparisons
comparing between species allows us to find evolutionary relationships
comparing between individuals of the same species allows us to tailor medical treatment to the individual
how can DNA sequencing be used in synthetic biology
knowing the sequence of a gene allows us to predict the sequence of amino acids that will code for the polypeptide it forms
this allows for development in synthetic biology
what is DNA profiling
identifying unique areas of a persons DNA to create a profile individual to them
give uses of DNA profiling
forensics=DNA obtained during crime investigations can be compared to that of victims or suspects
medicine=to screen for particular base sequence in order to identify heritable diseases
how can we amplify DNA fragments to sequence them
using polymerase chain reaction (PCR) makes millions of copies of a fragment which is then cut at different lengths to be sequenced
describe the reaction mixture in the first stages of PCR
contains DNA fragment to be amplified primers that are complementary to the start of the fragment
free nucleotides to match up to exposed bases
DNA polymerase to make new DNA
summarise the process of amplifying DNA fragments using PCR
- heated to break apart strands
- cooled to allow primers to bind
- heated again to activate DNA polymerase and allow free nucleotides to join
- new DNA acts as template for next cycle
how is gel electrophoresis used in DNA profiling
DNA fragments of varying lengths are placed at one end of a slab of gel
electric current is applied-DNA fragments move towards the other end of gel
shorter fragments travel further
the pattern of bands created is unique to each individual
what is meant by genetic engineering
where a DNA fragment from one organism is inserted into the DNA of another organism
done through a vector and a host cell
summarise the process of isolating a DNA fragment
restriction enzymes cut DNA at specific sequences
using particular enzymes allows you to cut specific parts
summarise process of inserting DNA fragment into a vector
plasmid is used as vector and is cut using same restriction enzymes so ends are complementary
DNA ligase joins fragment and plasmid together
summarise process of inserting vector into a host cell
host cells mixed with vectors in an ice cold solution
shocked to increase permeability of cell membrane which encourages cell to take up vectors
what is gene therapy
replacing a faulty allele with a normal one
germ line or somatic gene therapy
