Recitation 11: Cancer Genetics Flashcards
DNA microarrays are clarifying the … of health and disease and speeding … discovery. They could also hasten the day when customer tailored treatment plans replace a one-size-fits-all approach to health care
molecular roots; drug
cancer discussed is called
diffuse large B cell lymphoma
large B cell lymphoma comes in different forms caused by
distinct molecular abnormalities
DNA microarray is also known as
DNA chip
DNA microarray enabled researchers to distinguish between long- and short- term survivors based on differences in the overall pattern of activity exhibited by hundreds of … in their …. at the time of diagnosis
genes; malignant cells
DNA microarray should lead to a … able to identify the patients in greatest danger
diagnostic test
Microarrays are beginning to revolutionize how scientists explore the operation of … in the body and the … that underlie medical disorders
normal cells; molecular aberrations
Microarrays will pave the way for …, more … diagnoses of many conditions and to help doctors personalize medical care–that is, tailor therapies to the exact … of disease in each person and select the drugs likely to work best, with the mildest side effects, in those individuals
faster; accurate
Arrays all assess the …. of genetic material in a tissue sample, and consist of a lawn of … DNA molecules (probes) that are tethered to a wafer often no bigger than a thumbprint.
composition; single-stranded;
Arrays also capitalize on
complementary base pairing
DNA microarrays can track tens of thousands of complementary base pair reactions in … on a … This is possible because each kind of probe sits at an assigned spot within a chekerboardlike grid on the chip and the DNA/RNA molecules that get poured over the array carry a … or other label that can be detected by a scanner, which converts the raw data into a color coded readout
parallel; single chip; fluorescent tag
The DNA on a chip is compared with DNA in a tissue sample to determine …. or to decipher the order of … in as yet … strings of DNA
which genes are in the sample; code letters; unsequenced
Arrays can be used not only to assess the presence/sequence of genes in a sample but the …, or …, of those genes
expression; activity level
The genotype approach has been used to … in different organisms to find clues to … and to compare the genes in … with those in … to uncover subtle differences in composition/number
compare the genes; evolutionary history; tumors; normal tissues;
the chips can be designed to detect specific … or to measure … in tissue samples
genes; gene activity
…, which have great promise as diagnostic devices and as aids to biological research, are being developed as well.
protein arrays
another major use of arrays
expression profiling
expression profiles are produced by measuring the amounts of different … Generally, the more copies of this a cell makes, the more copies of … it will make, so these quantities can indirectly indicate the … and … present
mRNAs in a tissue sample; proteins; types; amounts of proteins
By using the genome as a sensor pad
to detect activity changes in a cell’s various
genes, scientists can gain exquisitely
detailed “snapshots” of how a cell’s functions
have been
altered by drugs or disease
states
Cell biologists
like it because knowledge of the proteins
that predominate after a tissue is exposed
to different conditions can provide insight
into how the tissue normally ….and what goes wrong
when …
compensates
for disruptions; diseases develop
Expression arrays can also be used to learn the … of genes that have recently been discovered
functoins
guilt-by-association method: method using arrays based on idea that no gene is an
island
pharmaceuticals use expression profiling to pick out and eliminate drug candidates that are likely to produce
unacceptable side effects
experiment is using expression profiles to determine if a protease inhibitor (used for HIV), …., produced some of its side effects by acting on the …
ritonavir; liver
they produced expression profiles of … exposed to an assortment of compounds that can be toxic to the liver, then grouped the compounds according to similarities of expression signatures. They delivered ritonavir to rat livers and compared the resulting expression profiles with those developed earleir
rat liver tissue
they found that ritonavir raises … levels in the liver by elevating the liver’s … and inhibiting its breakdown of …
lipid; synthesis of lipids; lipid-containing proteins
proto-oncogenes produce proteins that are involved in … the cell cycle. mutations in these genes tend to cause either an … of protein (…) or a protein to be … (pushing the cell cycle forward even in the absence of a signal to divide, e.g. growth factor)
promoting; over-production; over-expression; constitutively active
tumor suppressor genes: put the … on the cell cycle, usually at key checkpoints. Mutations in tumor suppressor genes that contribute to carcinogenesis can cause either abnormally … levels of protein or no … (…) at all. A mutation like this could allow a damaged or rogue cell to divide when it shouldnt
low; functional protein; under-expression
genome-maintenance genes include the … gene (which helps extend the life of a chromosome, and, consequently, the number of … that it can undergo) and DNA … genes (which keep the level of … in all genes low)
telomerase; cell division cycles; repair; mutations
