Genomic sequencing Flashcards
What is the genome
An organisms genome is the genetic information encoded in the DNA of a complete set of chromosomes. It is the entire hereditary information encoded in DNA.
Genomics
The study of genomes.
In order to study genomes the entire DNA of the organism must be sequenced.
Genomic sequencing
Determines the order of nucleotide bases in a section of DNA - this can be for individual genes and entire genomes.
How is the genome sequenced?
Sanger sequencing - process discovered by Fred Sanger, was used for around 40 years however is now slower and inefficient compared to modern methods.
Modern methods to find the sequence of the genome.
Computer programmes are used to find base sequences by looking for sequences similar to known genes.
Bioinformatics
Branch of science which combines statistical analysis and computer technology in order to study and sequence data.
It allows comparison of genomes from different species can be used to investigate evolutionary biology, inheritance and personalised medicine.
Which genomes are sequenced?
Disease causing organisms (pathogens)
Pest species
Model organisms - organisms which possess genes that are the same to that of humans.
Model organism examples
E.coli
Drosophila melanogaster
Mus musculus
Comparative genomics
Genomes that have been sequenced can be compared - they could be
From a different species
Individuals of the same species
Between cancerous and normal cells.
Comparison of genomes reveals
that DNA sequences of important genes are highly conserved (similar) across organisms.
How can the relatedness of organisms be found by comparison of DNA sequencing?
The greater the number of conserved DNA sequences in common equated to the more related the groups are.
SNPs
Single nucleotide polymorphisms are variation in DNA sequences that affect a single base pair which have arisen due to substitution mutations.