Case unit 3 Flashcards
What is a genome
the entire DNA content of an organism or cell
what is an exome
the regions of the genome that code for proteins
what is genetic linkage
a measure of how resistant to recombinant a genetic marker and phenotype are
whats does genetic linkage detect
the chromosonal location of diseased genes
what is linkage
tendancy for genes and other genetic markers to be inherited together because of their location near one another on the same chromosome
what is a genetic marker
segment of DNA with an idenitfied physical location on a chromosome whose inheritence can be followed
what does a LOD score show
whether two loci lie near each other and are likely to be inherited together
when is trio analysis used
in diseases where no explaniation can be given
rare and unknown
how does trio analysis work
whole exome is sequenced
looks at approx 20,000 genes, first those genes known to be related then all genes
look for variants and compare against parents
whats is GWAS
an observational study, idenitfy over expressed SNPs in diseased patients
what is the benefit of GWAS
helps understand diseased mechanisms
understand development
identify those at risk
why is whole genome sequencing good
allows you to look at one change e.g deletion
how does GWAS work
we have the geome sequence for over 10,000 SNPs
coat chip with single stranded DNA containing SNPs
hybridise labelled gDNA from individuals
locate genes by showing up on chip
describe a GWAS case control study
purify DNA from 1000s of individuals
map using SNPs chips to identify
looks for overrepersentaion of SNPs in pateints
if lots of people have that genetic difference then it is near that gene
anaylse on computers and mark out genes that have over representaion
what is a biobank
people donate tissue samples
all sorts of varaiables are measured over the years
prospective cohort study
