Transcript *** 1 - Institute of Statistical Science, Academia Sinica

Some stories about evolution
Wen-Ping Hsieh
[email protected]
Institute of Statistics
National Tsing Hua University
Sep. 6, 2012
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Outline
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Introduction to genetics
Genetic polymorphisms
Y-chromosome Adam and Mitochondria Eve
Human genome diversity
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A Quick Introduction to Genetics
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DNA->RNA->Protein
Recombination
Mutation
Polymorphism
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Source: Wikipedia
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http://www.accessexcellence.org/RC/VL/GG/central.php
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Recombination Rate
• There are only a few
crossover events
occurred to each
human chromosome in
each meiosis.
• Recombination rate is
higher between two
close loci.
• Recombination rate is
not consistent across
chromosomes.
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DNA Polymorphisms
• Single Nucleotide Polymorphism (SNP)
• Microsatellites or Short Tandem Repeats (STR)
• Insertion and deletion
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Fossil Evidence of Human Evolution
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Study of Blood Groups
• Blood type ABO
• Different allele frequency across populations
Region
A
B
O
Europe
27
8
65
British
25
8
67
Italian
20
7
73
Basques
23
2
75
East Asian
20
19
61
African
18
13
69
Indigenous
American
1.7
0.3
98
Indigenous
Australian
22
2
76
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Classification of Populations
• With polymorphisms of ABO, RH and MN
blood types, scientists can easily distinguish
populations of the five continents. (The study
of William Boyd)
• When we count in more features, almost all
populations can be distinguished. That is,
people live in Taipei can be genetically
different from people in Taichung if we
consider enough numbers of genetic features.
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適者生存 or 幸者生存
• Sickle Cell Anemia and Malaria defense
– Natural selection
• O blood type of native American
– Founder's effect
– Natural selection: Syphilis epidemics
• Neutral genes
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Forces of Evolution
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Mutation
Selection
Random drift
Migration
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Genetic Distances
• How different are two individuals?
– Difference between parents and children
– Difference between grandparents and
grandchildren
– Difference between any two unrelated persons.
• How different are two populations?
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Genetic Distance among Five
Continents
• The genetic distance was calculated from 100
genes for 15 Groups (three groups in each
continent).
非洲
大洋洲
美洲
大洋洲
24.7
美洲
22.6
14.6
歐洲
16.6
13.5
9.5
亞洲
20.6
10.0
8.7
歐洲
9.7
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Phylogeny Tree
亞洲
美洲
歐洲
大洋洲
非洲
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Y chromosome and Mitochondria
• Y chromosome can be traced to back to one man
in Africa. That specific male is called the Scientific
Adam.
• Both men and women carry mitochondria but
only Moms pass it along. Hence, all our
mitochondria can be traced to one single woman
in Africa and she is called the Scientific Eve.
• Both appeared at around 144,000 years ago.
• Haplogroups
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Recent Viewpoint
Meet the Denisovans, indigenous Australia's Siberian kin Source: The Australian 17
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How to Construct Phylogeny Tree
• Distance-based
– Neighbor-joinning
– UPGMA
• Maximum parsimony
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Evolutionary History of Human
• DNA consists more information than fossils.
• The rules of DNA change is a lot more simpler
than the metrics measured from fossils.
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European Haplogroups of mtDNA
West Britain and Scandinavia
http://freepages.genealogy.rootsweb.ancestry.com/~jswdna/haplogroupn.gif
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European Haplogroups of mtDNA
Central and Eastern Europe, France, England
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European Haplogroups of mtDNA
All around Europe
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European Haplogroups of mtDNA
Northern Scandinavia, Saami
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European Haplogroups of mtDNA
Eastern Baltic Sea, Ireland and the west of Britain
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European Haplogroups of mtDNA
Ötzi the Iceman, Northern Italy, Around the Mediterranean
32% of people with Ashkenazi Jewish ancestry
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European Haplogroups of mtDNA
Mediterranean, Greece, Italy/Sardinia and Spain
Ireland, England-Wales, Scotland
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The Genographic Project
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Interactive Trail for the
Journey of Mankind
http://www.bradshawfoundation.com/journey/
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Migration of Austronesian (南島語系)
Source: Wiki
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Inference with Y chromosome
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Other Side Stories
• Y-chromosomal Aaron
– Haplogroup J-P58 consist of more than 50% of
Kohanim. It infers the most recent common
ancestor living around 3200(± 1100) years ago.
– Haplogroup J-M410 consist of around 14% of
Kohanim. It infers the most recent common
ancestor living around 4200(± 1300) years ago.
• mtDNA and Y chromosome in Venezuela
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Conclusion
• 統計是遺傳研究不可或缺的一部份
• 遺傳則是統計研究裡面充滿想像與驚奇的
旅程
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References
• Geni, Popoli e Lingue (追蹤亞當夏娃) by Luigi
Luca Cavalli-Sforza (2003)
• The journey of man: a genetic odyssey.
Spencer Wells. (2002)
• The seven daughters of Eve (夏娃的七個女兒).
Bryan Sykes. (2001)
• National Geographic: The human family tree
http://topdocumentaryfilms.com/humanfamily-tree/
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