recombinant DNA technology Flashcards
what is a mutation?
permanent alterations in DNA sequence
what causes a mutation?
. errors in DNA synthesis that occur spontaneously at low frequency
. chemical mutagens
. ionising radiation
what are the 3 types of substitiution mutations?
conseravtive, non-conservative, no mutation
define a conservative mutation
amini acid replaced by one with similar properties so may not alter the function of the protein
define a non-conservative mutation
amino acid replaced by 1 which has different propertities, resulting in mutated protein and disease phenotype
what is the result of a mutation which is due to a inserted or deleted base?
frame-shift - synthesis of a prtein which has a completely different sequence downstream of the mutation`
what is the purpose of gene cloning?
produces large number of oarticular piece of DNA
briefly describe the process of gene cloning
. gene isolated using a restriction enzyme followed by gel electrophoresis
. gene inserted into plasmid
. plasmid inserted into bacterium, and bacterium allowed to grow and produce many copies oth the gene
. gene re-isloated using same restriction enzyme
what do restriction enzymes do?
cut double stranded DNA at specific sequences
what is the name given to the structural aspect of a DNA sequencee cut by a restriction enzyme that allows the DNA fragmemts to re-associate by base pairing?
stick ends
which enzyme rejoins DNA fragments?
ligase
name the 2 generations of DNA sequencing technology
sanger sequencing and high-throughput sequencing
when is sanger sequencing most commonly used?
small scale projects (single genes)
what are dNTPs?
building blocks of DNA
What are ddNTPs?
modified nucleoties that terminate DNA strand elongation
