genomes as the hub of biology n.
Download
Skip this Video
Loading SlideShow in 5 Seconds..
Genomes as the Hub of Biology PowerPoint Presentation
Download Presentation
Genomes as the Hub of Biology

Loading in 2 Seconds...

play fullscreen
1 / 15

Genomes as the Hub of Biology - PowerPoint PPT Presentation


  • 105 Views
  • Uploaded on

Genomes as the Hub of Biology. UNIT 2. The hub of biology. As biologists, we seek not only to understand how a single organism works, but how organisms interact. The same is true for genomes. To see life clearly, we must understand how genomes relate to one another.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about 'Genomes as the Hub of Biology' - maalik


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
the hub of biology
The hub of biology
  • As biologists, we seek not only to understand how a single organism works, but how organisms interact.
  • The same is true for genomes.
  • To see life clearly, we must understand how genomes relate to one another.
    • Within an individual (cell to cell, developmental changes in gene expression)
    • Within/among populations (variation and change)
    • Among species (evolutionary relationships; understanding how genomes evolve; genome interactions via disease, predation, etc.)
slide3

Genomics and development

  • Donut analogy
  • Monodelphisdomestica
  • Divergence from humans ~180 mya
  • ~18-20k genes
  • Only eightlack human homologs
  • The differences between us is primarily due to differences in regulation of the same suite of genes.
  • Example = HOX genes – responsible for anterior/posterior patterning in flies, humans, C. elegans.
slide4

Genomics and behavior

  • C. elegansdining behavior:
    • Wild-type Australian taxa congregate to eat
    • British wild-type eat separately
    • Traces to a single AA mutation in a transmembrane protein, NPR-1
  • Changes in CREB (cyclic AMP response element binding protein) impact learning and memory in flies and mouse.
  • Multiple genes are associated with schizophrenia
  • Severe, prolonged depression is associated with being homozygous for the short allele of the serotonin transporter, 5-HTT
slide5

Genomics and populations

  • Phenotypic variation in populations is the raw material of evolution
  • Genomic variation is the raw material for phenotypic variation
  • Founder effects and bottlenecks can reduce variation and impact evolutionary processes in populations
  • Genomic variation can be measured in multiple ways
slide6

Genomics and populations

  • SNPs – Single Nucleotide Polymorphisms
    • Single base variations among genomes
  • STRs – Short Tandem Repeats aka microsatellites
  • Populations with long evolutionary histories tend to have higher variation
    • An African origin for humans
    • 22 divergent lineages in Africa, three outside of Africa
slide7

Genomics and populations

  • Mitochondrial haplotypes
slide8

Genomics and populations

  • SNPs tell a story of admixture in human history
slide9

Genomics and populations

  • SNPs tell the story of admixture in human history
  • Comparison of the Neanderthal and modern human genomes reveal an influx of novel alleles in non-African modern humans
  • Those novel alleles are similar to Neanderthal alleles
slide10

Genomics and populations

  • SNPs tell the story of admixture in human history
  • Four possible scenarios
    • 1 - hybridization between ancient ancestor and Neanderthals
    • 2 – hybridization of ancient European and Asian populations with Neanderthals
    • 3 – hybridization between Neanderthals and a common non-African ancestor
    • 4 – persistent population substructure shared between Neanderthals and modern humans
slide11

Genomics and populations

  • SNPs tell the story of population sizes in human history
  • PSMC (pairwise sequential Markovian coalescent) analysis
    • A diploid genome sequence harbors hundreds of thousands of independent loci, each with its own TMRCA.
    • Use local densities of heterozygous sites to reconstruct the TMRCA distribution across the autosomes and chromosome X
    • Parameters include the scaled mutation rateand recombination rate, and piecewise constant ancestral population sizes
    • If you know two, you can estimate the third.

The population sizes inferred

from autosomes of six individuals

~10-60 kya

Severe bottleneck in Eurasian

populations

Less severe in African populations

slide12

Genomics and species

  • Species are a fundamental unit of evolution
    • Despite the fact that no one can truly define what a species is.
  • Genomics can influence our understanding of species by:
    • Providing large scale data sets to determine species relationships
      • Buddenbrockiaplumatellae
      • 129 protein alignments

nematodes

slide13

Genomics and species

  • Species are a fundamental unit of evolution
    • Despite the fact that no one can truly define what a species is.
  • Genomics can influence our understanding of species by:
    • Providing large scale data sets to determine species relationships
      • Buddenbrockiaplumatellae
      • 129 protein alignments
    • Quantitative measurements of the divergences between species
      • Crocodile vs. alligator whole genome pairwise alignment
      • 93.3% identity (assuming G = 20 yrs, TMRCA = 100 my)
      • μ(Crocodylia) = ~6.7 x 10 -9
slide14

Genomics and species

  • Reversing extinctions?
      • http://www.livescience.com/40264-how-to-bring-back-the-woolly-mammoth-infographic.html
slide15

Genomics and species

  • How big are genomes?