| 61. |
- Hedenstierna-Jonson, Charlotte, 1971-, et al.
(författare)
-
A female Viking warrior confirmed by genomics
- 2017
-
Ingår i: American Journal of Physical Anthropology. - : Wiley. - 0002-9483 .- 1096-8644. ; 164:4, s. 853-860
-
Tidskriftsartikel (refereegranskat)abstract
- ObjectivesThe objective of this study has been to confirm the sex and the affinity of an individual buried in a well-furnished warrior grave (Bj 581) in the Viking Age town of Birka, Sweden. Previously, based on the material and historical records, the male sex has been associated with the gender of the warrior and such was the case with Bj 581. An earlier osteological classification of the individual as female was considered controversial in a historical and archaeological context. A genomic confirmation of the biological sex of the individual was considered necessary to solve the issue.Materials and methodsGenome-wide sequence data was generated in order to confirm the biological sex, to support skeletal integrity, and to investigate the genetic relationship of the individual to ancient individuals as well as modern-day groups. Additionally, a strontium isotope analysis was conducted to highlight the mobility of the individual.ResultsThe genomic results revealed the lack of a Y-chromosome and thus a female biological sex, and the mtDNA analyses support a single-individual origin of sampled elements. The genetic affinity is close to present-day North Europeans, and within Sweden to the southern and south-central region. Nevertheless, the Sr values are not conclusive as to whether she was of local or nonlocal origin.DiscussionThe identification of a female Viking warrior provides a unique insight into the Viking society, social constructions, and exceptions to the norm in the Viking time-period. The results call for caution against generalizations regarding social orders in past societies.
|
|
| 62. |
- Hervella, M., et al.
(författare)
-
The mitogenome of a 35,000-year-old Homo sapiens from Europe supports a Palaeolithic back-migration to Africa
- 2016
-
Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 6
-
Tidskriftsartikel (refereegranskat)abstract
- After the dispersal of modern humans (Homo sapiens) Out of Africa, hominins with a similar morphology to that of present-day humans initiated the gradual demographic expansion into Eurasia. The mitogenome (33-fold coverage) of the Pestera Muierii 1 individual (PM1) from Romania (35 ky cal BP) we present in this article corresponds fully to Homo sapiens, whilst exhibiting a mosaic of morphological features related to both modern humans and Neandertals. We have identified the PM1 mitogenome as a basal haplogroup U6*, not previously found in any ancient or present-day humans. The derived U6 haplotypes are predominantly found in present-day North-Western African populations. Concomitantly, those found in Europe have been attributed to recent gene-flow from North Africa. The presence of the basal haplogroup U6* in South East Europe (Romania) at 35 ky BP confirms a Eurasian origin of the U6 mitochondrial lineage. Consequently, we propose that the PM1 lineage is an offshoot to South East Europe that can be traced to the Early Upper Paleolithic back migration from Western Asia to North Africa, during which the U6 lineage diversified, until the emergence of the present-day U6 African lineages.
|
|
| 63. |
|
|
| 64. |
- Hollfelder, Nina, et al.
(författare)
-
Northeast African genomic variation shaped by the continuity of indigenous groups and Eurasian migrations
- 2017
-
Ingår i: PLOS Genetics. - : Public Library of Science (PLoS). - 1553-7390 .- 1553-7404. ; 13:8
-
Tidskriftsartikel (refereegranskat)abstract
- Northeast Africa has a long history of human habitation, with fossil-finds from the earliest anatomically modern humans, and housing ancient civilizations. The region is also the gate-way out of Africa, as well as a portal for migration into Africa from Eurasia via the Middle East and the Arabian Peninsula. We investigate the population history of northeast Africa by genotyping ~3.9 million SNPs in 221 individuals from 18 populations sampled in Sudan and South Sudan and combine this data with published genome-wide data from surrounding areas. We find a strong genetic divide between the populations from the northeastern parts of the region (Nubians, central Arab populations, and the Beja) and populations towards the west and south (Nilotes, Darfur and Kordofan populations). This differentiation is mainly caused by a large Eurasian ancestry component of the northeast populations likely driven by migration of Middle Eastern groups followed by admixture that affected the local populations in a north-to-south succession of events. Genetic evidence points to an early admixture event in the Nubians, concurrent with historical contact between North Sudanese and Arab groups. We estimate the admixture in current-day Sudanese Arab populations to about 700 years ago, coinciding with the fall of Dongola in 1315/1316 AD, a wave of admixture that reached the Darfurian/Kordofanian populations some 400–200 years ago. In contrast to the northeastern populations, the current-day Nilotic populations from the south of the region display little or no admixture from Eurasian groups indicating long-term isolation and population continuity in these areas of northeast Africa.
|
|
| 65. |
- Hollfelder, Nina, et al.
(författare)
-
Patterns of African and Asian admixture in the Afrikaner population of South Africa
- 2020
-
Ingår i: BMC Biology. - : Springer Science and Business Media LLC. - 1741-7007. ; 18:1
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The Afrikaner population of South Africa is the descendants of European colonists who started to colonize the Cape of Good Hope in the 1600s. In the early days of the colony, mixed unions between European males and non-European females gave rise to admixed children who later became incorporated into either the Afrikaner or the Coloured populations of South Africa. Differences in ancestry, social class, culture, sex ratio and geographic structure led to distinct and characteristic admixture patterns in the Afrikaner and Coloured populations. The Afrikaner population has a predominant European composition, whereas the Coloured population has more diverse ancestries. Genealogical records previously estimated the contribution of non-Europeans into the Afrikaners to be between 5.5 and 7.2%. RESULTS: To investigate the genetic ancestry of the Afrikaner population today (11-13 generations after initial colonization), we genotyped approximately five million genome-wide markers in 77 Afrikaner individuals and compared their genotypes to populations across the world to determine parental source populations and admixture proportions. We found that the majority of Afrikaner ancestry (average 95.3%) came from European populations (specifically northwestern European populations), but that almost all Afrikaners had admixture from non-Europeans. The non-European admixture originated mostly from people who were brought to South Africa as slaves and, to a lesser extent, from local Khoe-San groups. Furthermore, despite a potentially small founding population, there is no sign of a recent bottleneck in the Afrikaner compared to other European populations. Admixture amongst diverse groups from Europe and elsewhere during early colonial times might have counterbalanced the effects of a small founding population. CONCLUSIONS: While Afrikaners have an ancestry predominantly from northwestern Europe, non-European admixture signals are ubiquitous in the Afrikaner population. Interesting patterns and similarities could be observed between genealogical predictions and our genetic inferences. Afrikaners today have comparable inbreeding levels to current-day European populations.
|
|
| 66. |
- Hollfelder, Nina, 1985-
(författare)
-
Population genetic history and patterns of admixture : Examples from northeastern and southern Africa
- 2018
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The origin of humans lies in Africa, as has been shown by archaeology, paleontology and genetics. Here, we can find the largest genetic diversity and the deepest split among human populations. African genetic diversity has been shaped by a long and complex history. In this thesis, I applied population genomic methods to investigate different aspects of the demographic history of Africa, specifically northeast and southern Africa.Both of these regions are population melting-pots, with many historically known major migrations.In northeast African populations, Eurasian admixture in central, northern, and eastern Sudanese populations was identified to be of Middle Eastern origin and the admixture time coincides with the Arab expansion. In northeast Africa I also studied alleles associated with lactase persistence, the ability to digest milk at an adult age. A wide diversity of these alleles was detected in Sudan, most commonly among pastoralists. The presence of a Middle Eastern LP-allele and absence of a European LP-allele is consistent with the admixture pattern observed in the first paper.I deciphered the patterns of genetic admixture in the Afrikaner population of South Africa and compared admixture patterns of the X-chromosome and autosomes to disentangle sex-biased admixture in southern African populations.The Afrikaner were shown to carry on average 5% non-European admixture, mostly from Khoe-San, East and South Asian sources. The admixture was sex-biased, with larger contributions from European males and admixture with Africans can be dated to 9-10 generations ago – fitting previous genealogical estimates of the age and the history of the population.Bantu-speaker/Khoe-San contact shows a pattern of female Bantu-speaker bias, which is conflicting with previous mtDNA and Y-chromosome studies. A change in mate-choice over time could explain this discrepancy.This thesis contributes to a deeper understanding of African demographic history in general and of some previously understudied populations and geographic areas in particular.
|
|
| 67. |
- Hollfelder, Nina, et al.
(författare)
-
The deep population history in Africa
- 2021
-
Ingår i: Human Molecular Genetics. - : Oxford University Press. - 0964-6906 .- 1460-2083. ; 30:R1, s. R2-R10
-
Forskningsöversikt (refereegranskat)abstract
- Africa is the continent with the greatest genetic diversity among humans and the level of diversity is further enhanced by incorporating non-majority groups, which are often understudied. Many of today's minority populations historically practiced foraging lifestyles, which were the only subsistence strategies prior to the rise of agriculture and pastoralism, but only a few groups practicing these strategies remain today. Genomic investigations of Holocene human remains excavated across the African continent show that the genetic landscape was vastly different compared to today's genetic landscape and that many groups that today are population isolate inhabited larger regions in the past. It is becoming clear that there are periods of isolation among groups and geographic areas, but also genetic contact over large distances throughout human history in Africa. Genomic information from minority populations and from prehistoric remains provide an invaluable source of information on the human past, in particular deep human population history, as Holocene large-scale population movements obscure past patterns of population structure. Here we revisit questions on the nature and time of the radiation of early humans in Africa, the extent of gene-flow among human populations as well as introgression from archaic and extinct lineages on the continent.
|
|
| 68. |
- Hollfelder, Nina, et al.
(författare)
-
The Genetic Variation of Lactase Persistence Alleles in Sudan and South Sudan
- 2021
-
Ingår i: Genome Biology and Evolution. - : Oxford University Press. - 1759-6653. ; 13:5
-
Tidskriftsartikel (refereegranskat)abstract
- Lactase persistence (LP) is a well-studied example of a Mendelian trait under selection in some human groups due to gene-culture coevolution. We investigated the frequencies of genetic variants linked to LP in Sudanese and South Sudanese populations. These populations have diverse subsistence patterns, and some are dependent on milk to various extents, not only from cows but also from other livestock such as camels and goats. We sequenced a 316-bp region involved in regulating the expression of the LCT gene on chromosome 2, which encompasses five polymorphisms that have been associated with LP. Pastoralist populations showed a higher frequency of LP-associated alleles compared with nonpastoralist groups, hinting at positive selection also among northeast African pastoralists. Among the LP variants, the -14009:G variant occurs at the highest frequency among the investigated populations, followed by the -13915:G variant, which is likely of Middle Eastern origin, consistent with Middle Eastern gene flow to the Sudanese populations. There was no incidence of the “East African” LP allele (-14010:C) in the Sudanese and South Sudanese groups, and only one heterozygous individual for the “European” LP allele (-13910:T), suggesting limited recent admixture from these geographic regions. The Beja population of the Beni Amer show three different LP variants at substantial and similar levels, resulting in one of the greatest aggregation of LP variants among all populations across the world.
|
|
| 69. |
- Holm, Alexander, et al.
(författare)
-
Patients' perspective on prostatic artery embolization : A qualitative study
- 2021
-
Ingår i: SAGE Open Medicine. - : SAGE Open. - 2050-3121. ; 9, s. 1-6
-
Tidskriftsartikel (refereegranskat)abstract
- Objectives: The aim was to describe the patients' experience of undergoing prostatic artery embolization.Methods: A retrospective qualitative interview study was undertaken with 15 patients of mean age 73 years who had undergone prostatic artery embolization with a median duration of 210 min at two medium sized hospitals in Sweden. The reasons for conducting prostatic artery embolization were clean intermittent catheterization (n = 4), lower urinary tract symptoms (n = 10) or haematuria (n = 1). Data were collected through individual, semi-structured telephone interviews 1-12 months after treatment and analysed using qualitative content analysis.Results: Four categories with sub-categories were formulated to describe the results: a diverse experience; ability to control the situation; resumption of everyday activities and range of opinions regarding efficacy of outcomes. Overall, the patients described the procedure as painless, easy and interesting and reported that while the procedure can be stressful, a calm atmosphere contributed to achieving a good experience. Limitations on access to reliable information before, during and after the procedure were highlighted as a major issue. Practical ideas for improving patient comfort during the procedure were suggested. Improved communications between treatment staff and patients were also highlighted. Most patients could resume everyday activities, some felt tired and bruising caused unnecessary worry for a few. Regarding functional outcome, some patients described substantial improvement in urine flow while others were satisfied with regaining undisturbed night sleep. Those with less effect were considering transurethral resection of the prostate as a future option. Self-enrolment to the treatment and long median operation time may have influenced the results.Conclusions: From the patients' perspective, prostatic artery embolization is a well-tolerated method for treating benign prostate hyperplacia.
|
|
| 70. |
- Huang, Lucy, et al.
(författare)
-
Haplotype variation and genotype imputation in African populations
- 2011
-
Ingår i: Genetic Epidemiology. - : Wiley. - 0741-0395 .- 1098-2272. ; 35:8, s. 766-780
-
Tidskriftsartikel (refereegranskat)abstract
- Sub-Saharan Africa has been identified as the part of the world with the greatest human genetic diversity. This high level of diversity causes difficulties for genome-wide association (GWA) studies in African populationsfor example, by reducing the accuracy of genotype imputation in African populations compared to non-African populations. Here, we investigate haplotype variation and imputation in Africa, using 253 unrelated individuals from 15 Sub-Saharan African populations. We identify the populations that provide the greatest potential for serving as reference panels for imputing genotypes in the remaining groups. Considering reference panels comprising samples of recent African descent in Phase 3 of the HapMap Project, we identify mixtures of reference groups that produce the maximal imputation accuracy in each of the sampled populations. We find that optimal HapMap mixtures and maximal imputation accuracies identified in detailed tests of imputation procedures can instead be predicted by using simple summary statistics that measure relationships between the pattern of genetic variation in a target population and the patterns in potential reference panels. Our results provide an empirical basis for facilitating the selection of reference panels in GWA studies of diverse human populations, especially those of African ancestry.
|
|
