Molecular Genetics: Genomics

Question 1

genomics

Answer 1

science of sequencing, interpreting, and comparing whole genomes

Question 2

sequencing of genomes

Answer 2

similar to PCR and gel - run multiple cycles using ddNTPs until fragments of all lengths are acquired for that gene - run through tube gel and fluorescence picked up by laser

Question 3

short fragments in sequencing of genomes

Answer 3

pass through laser first - closer to 5’ end of DNA

Question 4

genome annotation

Answer 4

identifying gene location and strand within the genome

Question 5

genome annotation in prokaryotes

Answer 5

look for Open Reading Frame (sequence between start and stop codon)

Question 6

how to determine genetic code from ORF

Answer 6

predict two mRNAs (one for each strand), alter the mRNA reading frames (six total) and pick the one with no stop codons in the middle

Question 7

after ORF is found what is searched for

Answer 7

regulatory sequences upstream of the gene

Question 8

in prokaryotes relationship of genome size and gene number

Answer 8

correlate positively and with metabolic range

Question 9

genome annotating in eukaryotes

Answer 9

use reverse transcriptase to generate cDNA and compare to genomic sequence

Question 10

expressed sequence tags

Answer 10

sequenced cDNA

Question 11

why can’t we look for ORFs in eukaryotes

Answer 11

introns

Question 12

repetitive sequences in eukaryotic genome

Answer 12

transposable elements, microsatellites, minisatellites

Question 13

transposable elements

Answer 13

DNA sequences that can move around the genome - contains codes for proteins involved in copying/inserting of removal/insertion of itself

Question 14

how do eukaryotes control transposable elements

Answer 14

DNA methylation, chromatin condensation, RNAi

Question 15

microsatellites and minisatellites

Answer 15

(2-6bp) or (6-100bp) repetitive stretchs of DNA that can misallign during meiosis and cause unequal crossing over

Question 16

how are microsatellite and minisatellite repeats used in DNA fingerprinting

Answer 16

every person has two peaks (one for each chromosome) for every loci of repeats - one from each parent

Question 17

microarray

Answer 17

grid of single-stranded DNA sequences that are complementary for every coding or regulatory sequence

Question 18

how to use microarray

Answer 18

apply radiolabeled cDNA to microarray and observe fluorescence at each grid location to determine expression