1.8 Genomic Sequencing Flashcards
What is genomics?
study of genomes - involves determining the sequence of nucleotide base of organisms DNA - genomic sequencing and the relating this genetic info about genes to their functions
this process of genomics involves bioinformatics
What is bioinformatics?
combo of molecular biology statistical analysis and computer technology
allows scientists to rapidly map and analyse DNA sequences on a huge scale and compare them
What is genomics used to investigate?
evolutionary biology
inheritance
personalised medicine
What are the two steps of establishing the sequence of a genome?
cutting it into smaller chunks
putting the chunks back together
Explain these steps?
cutting the genome into smaller fragments using restriction endonucleases (restriction enzymes)
restriction endonucleases recognise specific short sequences called restriction sites and cut the DNA at every point this sequence appears
each restriction endonuclease is specific to its restriction site
Putting the pieces back together
two copies of genome are digested with different restriction endonucleases producing two sets of fragments
computer analysis of the fragment overlaps between the two sets of fragments all calculation of the active genome
What are comparative genomics?
this branch of genomics compares the sequenced genomes of :
members of different species
members of the same species
cancerous cells and normal cells
What is a single nucleotide polymorphism (SNP)?
variation on a DNA sequence that affects a single base pair
What is the use of SNP?
SNP maps will help scientists to identify and understand the workings of genes associated with diseases
What is conserved genetic sequences?
close comparison of genomes reveals important similarities
What are phylogenetics?
compares sequence data of different species to determine how related they are and when they diverged (split) from a common ancestor - isolated
Sequence divergence?
can be used along with the fossil record in drawing molecular clock graphs
Molecular clocks?
these diagrams based on the assumption that the mutation rate of genes leading to amino acid differences are constant throughout time
based on sequence differences of a particular protein
differences in sequences related to a protein in different species are graphed on one axis
other shows timescale of divergence based on relative sequence differences
Phylogenetic trees?
sequence data in combo with fossil evidence used to draw phylogenetic trees
Fossil evidence use in relation to phylogenetic trees?
to add timescales
Three domains of life?
prokaryotes
eukaryotes
archaea
