uu.seUppsala University Publications
Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Identification of local selective sweeps in human populations since the exodus from Africa
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Genetics and Pathology.
Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Genetics and Pathology.
2008 (English)In: Hereditas, ISSN 0018-0661, E-ISSN 1601-5223, Vol. 145, no 3, 126-137 p.Article in journal (Refereed) Published
Abstract [en]

Selection on the human genome has been studied using comparative genomics and SNP architecture in the lineage leading to modern humans. In connection with the African exodus and colonization of other continents, human populations have adapted to a range of different environmental conditions. Using a new method that jointly analyses haplotype block length and allele frequency variation (F-ST) within and between populations, we have identified chromosomal regions that are candidates for having been affected by local selection. Based on 1.6 million SNPs typed in 71 individuals of African American, European American and Han Chinese descent, we have identified a number of genes and non- coding regions that are candidates for having been subjected to local positive selection during the last 100 000 years. Among these genes are those involved in skin pigmentation (SLC24A5) and diet adaptation (LCT). The list of genes implicated in these local selective sweeps overlap partly with those implicated in other studies of human populations using other methods, but show little overlap with those postulated to have been under selection in the 5 - 7 myr since the divergence of the ancestors of human and chimpanzee. Our analysis provides focal points in the genome for detailed studies of evolutionary events that have shaped human populations as they explored different regions of the world.

Place, publisher, year, edition, pages
2008. Vol. 145, no 3, 126-137 p.
National Category
Medical and Health Sciences
Identifiers
URN: urn:nbn:se:uu:diva-95153DOI: 10.1111/j.0018-0661.2008.02054.xISI: 000259306900003PubMedID: 18667002OAI: oai:DiVA.org:uu-95153DiVA: diva2:169254
Available from: 2006-11-17 Created: 2006-11-17 Last updated: 2012-02-16Bibliographically approved
In thesis
1. Genome Variation in Human Populations: Exploring the Effects of Demographic History and the Potential for Mapping of Complex Traits
Open this publication in new window or tab >>Genome Variation in Human Populations: Exploring the Effects of Demographic History and the Potential for Mapping of Complex Traits
2006 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

A major challenge in human genetics is to understand the genetic variation underlying common diseases. In this thesis, I focus on forces creating differences between individuals and genomic regions, methods for characterizing genomic variation, and the association between genomic and phenotypic variation. Genetic markers are widely used to locate genes associated with different phenotypes. In my first paper, I describe novel algorithms for automatic genotype determination of microsatellite markers, a procedure which is currently both time-consuming and error prone.

The co-segregation of genetic markers in a population leads to non-random association of alleles at different loci - linkage disequilibrium (LD). LD varies throughout the genome and differs between populations due to factors such as their demographic history. In my second paper, I discuss the increased power, for mapping of human traits, that results from studying a population with appreciable levels of LD such as is found in the Swedish Sami population.

Lately, large-scale analyses of single nucleotide polymorphisms (SNPs) have become available and efforts have been made to identify a set of SNPs, which captures most of the genome variation in a population (tagSNPs). In my third paper, I describe the limitations of this approach when applied to data from an independent population sample of randomly ascertained SNPs. The transferability of tagSNPs between populations is poor, presumably due to variation in allele frequencies and the bias towards common SNPs used in most studies.

The level of genomic variation is influenced by population structure, recombination and mutation rate, as well as natural selection. During the exodus from Africa, humans have adapted to new environmental conditions. In my fourth paper, I describe a new method for identifying genomic regions carrying signatures of recent positive selection and apply this to an available dataset of millions of SNPs.

Place, publisher, year, edition, pages
Uppsala: Acta Universitatis Upsaliensis, 2006. 42 p.
Series
Digital Comprehensive Summaries of Uppsala Dissertations from the Faculty of Medicine, ISSN 1651-6206 ; 201
Keyword
Genetics, genetics, evolution, microsatellie, SNP, selection, linkage disequilibrium, haplotype, Genetik
Identifiers
urn:nbn:se:uu:diva-7293 (URN)91-554-6722-9 (ISBN)
Public defence
2006-12-08, Rudbecksalen, Rudbeck Laboratory, Dag Hammarskjölds väg 20, Uppsala, 13:15
Opponent
Supervisors
Available from: 2006-11-17 Created: 2006-11-17 Last updated: 2011-01-20Bibliographically approved

Open Access in DiVA

No full text

Other links

Publisher's full textPubMed

Authority records BETA

Johansson, Åsa

Search in DiVA

By author/editor
Johansson, Åsa
By organisation
Department of Genetics and Pathology
In the same journal
Hereditas
Medical and Health Sciences

Search outside of DiVA

GoogleGoogle Scholar

doi
pubmed
urn-nbn

Altmetric score

doi
pubmed
urn-nbn
Total: 741 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf