Flashcards in 1-36 FISH, Microarrays and Next Generation Sequencing (NGS) Deck (8):
explain the technique of FISH
flourecence in situ hybridization
DNA probes are labeled wtih flourescent dyes and hybridized to chomrosomes.
-probes made for particular DNA sequences are specific to those sequences and cannot be used for other loci.
the results are observed with flourescent microscope
Fish in clinical setting
used to assay for the presence or absence of a gene of interest whose sequence is known
FISH when testing for a deletion
two different color probes will be used - one for control, and one for gene of interest
someone with no deletion should show four signals
someone with a deletion at the locus of interest should only produce 3
-two control signals
-one signal from chromsome without the deletion
contiguous gene syndromes
Contiguous gene syndromes are diseases that arise from deletions or duplications of regions of DNA that contain genes with generally unrelated functions.
describe microarray analysis
comparison of the quantity of nucleic acid sequence of interest to the quantity of a reference nucleic acid sequence of a known genetic complement
applications of microarray analysis
dna arrays - targets a specific gene of interest in order to genotype a patient
expression (RNA) arrays - targets mRNA sequences to determine which genes are being expressed in a cell
chromosome arrays - assay for chromosome abnormailities
microarrays are not effective in detecting
balances rearrangment, as the amount of DNA between the test and refernce will be the same