| 1. |
- Joshi, Peter K, et al.
(författare)
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Directional dominance on stature and cognition in diverse human populations
- 2015
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 523:7561, s. 459-462
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Tidskriftsartikel (refereegranskat)abstract
- Homozygosity has long been associated with rare, often devastating, Mendelian disorders, and Darwin was one of the first to recognize that inbreeding reduces evolutionary fitness. However, the effect of the more distant parental relatedness that is common in modern human populations is less well understood. Genomic data now allow us to investigate the effects of homozygosity on traits of public health importance by observing contiguous homozygous segments (runs of homozygosity), which are inferred to be homozygous along their complete length. Given the low levels of genome-wide homozygosity prevalent in most human populations, information is required on very large numbers of people to provide sufficient power. Here we use runs of homozygosity to study 16 health-related quantitative traits in 354,224 individuals from 102 cohorts, and find statistically significant associations between summed runs of homozygosity and four complex traits: height, forced expiratory lung volume in one second, general cognitive ability and educational attainment (P < 1 × 10(-300), 2.1 × 10(-6), 2.5 × 10(-10) and 1.8 × 10(-10), respectively). In each case, increased homozygosity was associated with decreased trait value, equivalent to the offspring of first cousins being 1.2 cm shorter and having 10 months' less education. Similar effect sizes were found across four continental groups and populations with different degrees of genome-wide homozygosity, providing evidence that homozygosity, rather than confounding, directly contributes to phenotypic variance. Contrary to earlier reports in substantially smaller samples, no evidence was seen of an influence of genome-wide homozygosity on blood pressure and low density lipoprotein cholesterol, or ten other cardio-metabolic traits. Since directional dominance is predicted for traits under directional evolutionary selection, this study provides evidence that increased stature and cognitive function have been positively selected in human evolution, whereas many important risk factors for late-onset complex diseases may not have been.
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| 2. |
- Lewis, Nicola S., et al.
(författare)
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Influenza A virus evolution and spatio-temporal dynamics in Eurasian wild birds : a phylogenetic and phylogeographical study of whole-genome sequence data
- 2015
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Ingår i: Journal of General Virology. - : Microbiology Society. - 0022-1317 .- 1465-2099. ; 96, s. 2050-2060
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Tidskriftsartikel (refereegranskat)abstract
- Low pathogenic avian influenza A viruses (IAVs) have a natural host reservoir in wild waterbirds and the potential to spread to other host species. Here, we investigated the evolutionary, spatial and temporal dynamics of avian IAVs in Eurasian wild birds. We used whole-genome sequences collected as part of an intensive long-term Eurasian wild bird surveillance study, and combined this genetic data with temporal and spatial information to explore the virus evolutionary dynamics. Frequent reassortment and co-circulating lineages were observed for all eight genomic RNA segments over time. There was no apparent species-specific effect on the diversity of the avian IAVs. There was a spatial and temporal relationship between the Eurasian sequences and significant viral migration of avian lAVs from West Eurasia towards Central Eurasia. The observed viral migration patterns differed between segments. Furthermore, we discuss the challenges faced when analysing these surveillance and sequence data, and the caveats to be borne in mind when drawing conclusions from the apparent results of such analyses.
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| 3. |
- Wille, Michelle, et al.
(författare)
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Where do all the subtypes go? : Temporal dynamics of H8-H12 influenza A viruses in waterfowl
- 2018
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Ingår i: Virus Evolution. - : Oxford University Press. - 2057-1577. ; 4:2
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Tidskriftsartikel (refereegranskat)abstract
- Influenza A virus (IAV) is ubiquitous in waterfowl. In the northern hemisphere IAV prevalence is highest during the autumn and coincides with a peak in viral subtype diversity. Although haemagglutinin subtypes H1-H12 are associated with waterfowl hosts, subtypes H8-H12 are detected very infrequently. To better understand the role of waterfowl in the maintenance of these rare subtypes, we sequenced H8-H12 viruses isolated from Mallards (Anas platyrhynchos) from 2002 to 2009. These rare viruses exhibited varying ecological and phylodynamic features. The Eurasian clades of H8 and H12 phylogenies were dominated by waterfowl sequences; mostly viruses sequenced in this study. H11, once believed to be a subtype that infected charadriiformes (shorebirds), exhibited patterns more typical of common virus subtypes. Finally, subtypes H9 and H10, which have maintained lineages in poultry, showed markedly different patterns: H10 was associated with all possible NA subtypes and this drove HA lineage diversity within years. Rare viruses belonging to subtypes H8-H12 were highly reassorted, indicating that these rare subtypes are part of the broader IAV pool. Our results suggest that waterfowl play a role in the maintenance of these rare subtypes, but we recommend additional sampling of non-traditional hosts to better understand the reservoirs of these rare viruses.
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