Lecture 6: Omics Approaches in Neuroscience Flashcards
What are major omics approaches?
genomics
transcriptomics
proteomics
metabolomics
epigenomics
miRNAomics
What is the central dogma of molecular biology?
The central dogma of molecular biology is a theory stating that genetic information flows only in one direction: from DNA, to RNA, to protein, or RNA directly to protein
What is genomics?
measuring of all the DNA
genome = complete set of DNA
this is the basis of our genetic material (very stable and easy to measure)
DNA is a double helix structure composed of 4 nucleotides
What are some structures that regulate DNA transcription?
once the DNA is open specific structures regulate transcription
transcription factors gives the cell identity, cause all genes are not transcribed
enhancer elements bind to transcription factors near the promotor region (specific regions in specific cells that allow transcription to happen)
What is the human genome project?
formally launched in 1990
international effort
completed 2003
cost $3 billion
now with modern costs can sequence a human genome for $600-1000
What is the Sanger Sequencing method of DNA sequencing?
use primer elongation with chain termination
originally measured with gel electrophoresis
can measure now with flurochromes using capillary gel electrophoresis
What is next generation sequencing?
can do in a day wat takes weeks in Sanger sequencing
passively parallel by measuring DNA fragments
require DNA to be fragmented into specific sized “reads”
during library preparation various sequences are added that are needed for the sequencing process (ex. primer sequences)
cutting things into fragments and measuring those fragments
What are the steps of next generation sequencing?
- sample pre-processing
- library preparation
- sequencing
- bioinformatics
Where to SNPs occur?
almost once in every 1,000 nucleotides
roughly 4 to 5 million SNPs in a person’s genome
to be classified as a SNP, a variant is found in at least 1 percent of the population
What methods do “Ancestry” and “23 and Me” use to help measure DNA?
phenotyping
based on sampling, SNP analysis, not full genome sequencing
What are the steps in genotyping and genome wide associations (GWAS)?
- data collection
- genotyping
- quality control
- imputation
- association testing
How is genotyping performed?
genotyping here done with microarray
much cheaper than sequencing
What is P-value?
p-value is the probability of an event happening due to chance
What is the definition of genomics and epigenomics?
the study of the DNA sequence and associated heritable biochemical modifications
What is the definition of transcriptomics?
the study of the RNA molecules present in a sample