| 1. |
- Ballantyne, Kaye N., et al.
(författare)
-
Toward Male Individualization with Rapidly Mutating Y-Chromosomal Short Tandem Repeats
- 2014
-
Ingår i: Human Mutation. - : John Wiley & Sons. - 1059-7794 .- 1098-1004. ; 35:8, s. 1021-1032
-
Tidskriftsartikel (refereegranskat)abstract
- Relevant for various areas of human genetics, Y-chromosomal short tandem repeats (Y-STRs) are commonly used for testing close paternal relationships among individuals and populations, and for male lineage identification. However, even the widely used 17-loci Yfiler set cannot resolve individuals and populations completely. Here, 52 centers generated quality-controlled data of 13 rapidly mutating (RM) Y-STRs in 14,644 related and unrelated males from 111 worldwide populations. Strikingly, greater than99% of the 12,272 unrelated males were completely individualized. Haplotype diversity was extremely high (global: 0.9999985, regional: 0.99836-0.9999988). Haplotype sharing between populations was almost absent except for six (0.05%) of the 12,156 haplotypes. Haplotype sharing within populations was generally rare (0.8% nonunique haplotypes), significantly lower in urban (0.9%) than rural (2.1%) and highest in endogamous groups (14.3%). Analysis of molecular variance revealed 99.98% of variation within populations, 0.018% among populations within groups, and 0.002% among groups. Of the 2,372 newly and 156 previously typed male relative pairs, 29% were differentiated including 27% of the 2,378 father-son pairs. Relative to Yfiler, haplotype diversity was increased in 86% of the populations tested and overall male relative differentiation was raised by 23.5%. Our study demonstrates the value of RMY-STRs in identifying and separating unrelated and related males and provides a reference database.
|
|
| 2. |
- Chaitanya, Lakshmi, et al.
(författare)
-
Collaborative EDNAP exercise on the IrisPlex system for DNA based prediction of human eye colour
- 2014
-
Ingår i: Forensic Science International. - : Elsevier. - 1872-4973 .- 1878-0326. ; 11, s. 241-251
-
Tidskriftsartikel (refereegranskat)abstract
- The IrisPlex system is a DNA-based test system for the prediction of human eye colour from biological samples and consists of a single forensically validated multiplex genotyping assay together with a statistical prediction model that is based on genotypes and phenotypes from thousands of individuals. IrisPlex predicts blue and brown human eye colour with, on average, >94% precision accuracy using six of the currently most eye colour informative single nucleotide polymorphisms (HERC2 rs12913832, OCA2 rs1800407, SLC24A4 rs12896399, SLC45A2 (MATP) rs16891982, TYR rs1393350, and IRF4 rs12203592) according to a previous study, while the accuracy in predicting non-blue and non-brown eye colours is considerably lower. In an effort to vigorously assess the IrisPlex system at the international level, testing was performed by 21 laboratories in the context of a collaborative exercise divided into three tasks and organised by the European DNA Profiling (EDNAP) Group of the International Society of Forensic Genetics (ISFG). Task 1 involved the assessment of 10 blood and saliva samples provided on FTA cards by the organising laboratory together with eye colour phenotypes; 99.4% of the genotypes were correctly reported and 99% of the eye colour phenotypes were correctly predicted. Task 2 involved the assessment of 5 DNA samples extracted by the host laboratory from simulated casework samples, artificially degraded, and provided to the participants in varying DNA concentrations. For this task, 98.7% of the genotypes were correctly determined and 96.2% of eye colour phenotypes were correctly inferred. For Tasks 1 and 2 together, 99.2% (1875) of the 1890 genotypes were correctly generated and of the 15 (0.8%) incorrect genotype calls, only 2 (0.1%) resulted in incorrect eye colour phenotypes. The voluntary Task 3 involved participants choosing their own test subjects for IrisPlex genotyping and eye colour phenotype inference, while eye photographs were provided to the organising laboratory and judged; 96% of the eye colour phenotypes were inferred correctly across 100 samples and 19 laboratories. The high success rates in genotyping and eye colour phenotyping clearly demonstrate the reproducibility and the robustness of the IrisPlex assay as well as the accuracy of the IrisPlex model to predict blue and brown eye colour from DNA. Additionally, this study demonstrates the ease with which the IrisPlex system is implementable and applicable across forensic laboratories around the world with varying pre-existing experiences.
|
|
| 3. |
- Enattah, Nabil Sabri, et al.
(författare)
-
Evidence of still-ongoing convergence evolution of the lactase persistence T-13910 alleles in humans
- 2007
-
Ingår i: American Journal of Human Genetics. - : Elsevier BV. - 0002-9297. ; 81:3, s. 615-625
-
Tidskriftsartikel (refereegranskat)abstract
- A single-nucleotide variant, C/T-13910, located 14 kb upstream of the lactase gene (LCT), has been shown to be completely correlated with lactase persistence (LP) in northern Europeans. Here, we analyzed the background of the alleles carrying the critical variant in 1,611 DNA samples from 37 populations. Our data show that the T-13910 variant is found on two different, highly divergent haplotype backgrounds in the global populations. The first is the most common LP haplotype (LP H98) present in all populations analyzed, whereas the others (LP H8-H12), which originate from the same ancestral allelic haplotype, are found in geographically restricted populations living west of the Urals and north of the Caucasus. The global distribution pattern of LP T-13910 H98 supports the Caucasian origin of this allele. Age estimates based on different mathematical models show that the common LP T-13910 H98 allele (similar to 5,000-12,000 years old) is relatively older than the other geographically restricted LP alleles (similar to 1,400-3,000 years old). Our data about global allelic haplotypes of the lactose-tolerance variant imply that the T-13910 allele has been independently introduced more than once and that there is a still-ongoing process of convergent evolution of the LP alleles in humans.
|
|
| 4. |
- Fellman, Vineta, et al.
(författare)
-
Screening of BCS1L mutations in severe neonatal disorders suspicious for mitochondrial cause
- 2008
-
Ingår i: Journal of Human Genetics. - : Springer Science and Business Media LLC. - 1434-5161 .- 1435-232X. ; 53:6, s. 554-558
-
Tidskriftsartikel (refereegranskat)abstract
- The BCS1L gene encodes a chaperone responsible for assembly of respiratory chain complex III (CIII). A homozygous point mutation (232A -> G) has been found as the genetic etiology for fetal growth retardation, amino aciduria, cholestasis, iron overload, lactic acidosis, and early death (GRACILE) syndrome (MIM 603358). Variable phenotypes have been found with other mutations. Our aim was to assess whether 232A -> G or other BCS1L mutations were present in infants (n = 21) of Finnish origin with severe, lethal disease compatible with mitochondrial disorder. A further aim was to confirm the GRACILE genotype-phenotype constancy (n = 8). Three new cases with homozygous 232A -> G mutation were identified; all had the primary GRACILE characteristics. No other mutations were found in the gene in other cases. All infants with GRACILE syndrome had the typical mutation. In conclusion, the rather homogenous population of Finns seems to have a specific BCS1L mutation that, as homozygous state, causes GRACILE syndrome, whereas other mutations are rare or not occurring. Thus, the novel clinical implication of this study is to screen for BCS1L mutations only if CIII is dysfunctioning or lacking Rieske protein, and to assess 232A -> G mutation in cases with GRACILE syndrome.
|
|
| 5. |
- Lazaridis, Iosif, et al.
(författare)
-
Ancient human genomes suggest three ancestral populations for present-day Europeans
- 2014
-
Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 513:7518, s. 409-
-
Tidskriftsartikel (refereegranskat)abstract
- We sequenced the genomes of a similar to 7,000-year-old farmer from Germany and eight similar to 8,000-year-old hunter-gatherers from Luxembourg and Sweden. We analysed these and other ancient genomes(1-4) with 2,345 contemporary humans to show that most present-day Europeans derive from at least three highly differentiated populations: west European hunter-gatherers, who contributed ancestry to all Europeans but not to Near Easterners; ancient north Eurasians related to Upper Palaeolithic Siberians(3), who contributed to both Europeans and Near Easterners; and early European farmers, who were mainly of Near Eastern origin but also harboured west European hunter-gatherer related ancestry. We model these populations' deep relationships and show that early European farmers had similar to 44% ancestry from a 'basal Eurasian' population that split before the diversification of other non-African lineages.
|
|
| 6. |
- Niemi, Marianna, et al.
(författare)
-
Temporal Fluctuation in North East Baltic Sea Region Cattle Population Revealed by Mitochondrial and Y-Chromosomal DNA Analyses
- 2015
-
Ingår i: PLOS ONE. - : Public Library of Science (PLoS). - 1932-6203. ; 10:5
-
Tidskriftsartikel (refereegranskat)abstract
- Background Ancient DNA analysis offers a way to detect changes in populations over time. To date, most studies of ancient cattle have focused on their domestication in prehistory, while only a limited number of studies have analysed later periods. Conversely, the genetic structure of modern cattle populations is well known given the undertaking of several molecular and population genetic studies. Results Bones and teeth from ancient cattle populations from the North-East Baltic Sea region dated to the Prehistoric (Late Bronze and Iron Age, 5 samples), Medieval (14), and Post-Medieval (26) periods were investigated by sequencing 667 base pairs (bp) from the mitochondrial DNA (mtDNA) and 155 bp of intron 19 in the Y-chromosomal UTY gene. Comparison of maternal (mtDNA haplotypes) genetic diversity in ancient cattle (45 samples) with modern cattle populations in Europe and Asia (2094 samples) revealed 30 ancient mtDNA haplotypes, 24 of which were shared with modern breeds, while 6 were unique to the ancient samples. Of seven Y-chromosomal sequences determined from ancient samples, six were Y2 and one Y1 haplotype. Combined data including Swedish samples from the same periods (64 samples) was compared with the occurrence of Y-chromosomal haplotypes in modern cattle (1614 samples). Conclusions The diversity of haplogroups was highest in the Prehistoric samples, where many haplotypes were unique. The Medieval and Post-Medieval samples also show a high diversity with new haplotypes. Some of these haplotypes have become frequent in modern breeds in the Nordic Countries and North-Western Russia while other haplotypes have remained in only a few local breeds or seem to have been lost. A temporal shift in Y-chromosomal haplotypes from Y2 to Y1 was detected that corresponds with the appearance of new mtDNA haplotypes in the Medieval and Post-Medieval period. This suggests a replacement of the Prehistoric mtDNA and Y- chromosomal haplotypes by new types of cattle.
|
|
| 7. |
- Nilsson, Martina, 1977-
(författare)
-
Mitochondrial DNA in Sensitive Forensic Analysis
- 2007
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Genetic profiling is commonly performed on the autosomes using multiple DNA markers. Although routine forensic DNA analysis is robust and based on reliable technologies, samples with degraded or limited amounts of DNA often fail. In these cases, the analysis of mitochondrial DNA (mtDNA) can be very valuable due to the high copy number per cell. This thesis describes evaluation and modifications of existing technologies that are useful in forensic DNA typing, mainly focusing on mtDNA.DNA quantities isolated from common evidence materials such as hairs, fingerprints and accessories were estimated using a real-time quantification assay. Knowledge of quantitative differences between materials can guide forensic scientists to perform the best analysis (Paper I).The current mtDNA analysis is based on hypervariable region (HVI/HVII) sequencing, which is the most rigorous and time-consuming forensic DNA analysis. Therefore, we evaluated the possibility to exclude individuals by screening for non-matching samples using the rapid and easy mtDNA Linear Array Assay (Paper II). The major disadvantage using mtDNA is the lower discrimination power compared to multiple nuclear DNA markers. In contrast to the nuclear genome, due to the uniparental (maternal) mode of inheritance, no individual has unique mtDNA. We investigated the possibility of increasing the discrimination power by using pyrosequencing technology to analyse parts of the coding region in addition to HVI/HVII (Paper III). Furthermore, the addition of coding mtDNA information was evaluated by comparing several recently published mtDNA coding region assays (Paper IV). Mixtures of DNA are common in forensic genetics due to contribution of DNA from several individuals, contamination or heteroplasmy. To resolve mixtures we have developed a pyrosequencing-based assay for the accurate quantification of the mtDNA mixture components (Paper V).In conclusion, this thesis describes several assays that are valuable in forensic genetics for DNA quantification, improved mtDNA analysis, and mtDNA mixture interpretation.
|
|
| 8. |
- Raitio, Mirja, et al.
(författare)
-
Y-chromosomal SNPs in Finno-Ugric-speaking populations analyzed by minisequencing on microarrays
- 2001
-
Ingår i: Genome Research. - : Cold Spring Harbor Laboratory. - 1088-9051 .- 1549-5469. ; 11:3, s. 471-482
-
Tidskriftsartikel (refereegranskat)abstract
- An increasing number of single nucleotide polymorphisms (SNPs) on the Y chromosome are being identified. To utilize the full potential of the SNP markers in population genetic studies, new genotyping methods with high throughput are required. We describe a microarray system based on the minisequencing single nucleotide primer extension principle for multiplex genotyping of Y-chromosomal SNP markers. The system was applied for screening a panel of 25 Y-chromosomal SNPs in a unique collection of samples representing five Finno--Ugric populations. The specific minisequencing reaction provides 5-fold to infinite discrimination between the Y-chromosomal genotypes, and the microarray format of the system allows parallel and simultaneous analysis of large numbers of SNPs and samples. In addition to the SNP markers, five Y-chromosomal microsatellite loci were typed. Altogether 10,000 genotypes were generated to assess the genetic diversity in these population samples. Six of the 25 SNP markers (M9, Tat, SRY10831, M17, M12, 92R7) were polymorphic in the analyzed populations, yielding six distinct SNP haplotypes. The microsatellite data were used to study the genetic structure of two major SNP haplotypes in the Finns and the Saami in more detail. We found that the most common haplotypes are shared between the Finns and the Saami, and that the SNP haplotypes show regional differences within the Finns and the Saami, which supports the hypothesis of two separate settlement waves to Finland.
|
|
| 9. |
- Sturk-Andreaggi, Kimberly
(författare)
-
Mitochondrial Genome Analysis Using Next Generation Sequencing for Forensic Applications
- 2022
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Mitochondrial DNA (mtDNA) analysis plays a specialized role in forensic applications, overcoming certain limitations of autosomal DNA markers. The high copy number and uniparental inheritance pattern of mtDNA are advantageous in cases involving shed hairs and aged skeletal elements, especially decades-old missing persons cases. Though the discriminatory power of mtDNA is limited by common haplotypes, next generation sequencing (NGS) offers feasible access to entire mitochondrial genome (mitogenome) data that can provide increased resolution of common haplotypes to unique sequences. The primary implementation challenge of mitogenome analysis is a lack of forensic-quality reference data, which are required to determine the evidentiary weight of a match. A better understanding of NGS methods and data analysis is also necessary to ensure the generation of reliable mitogenome data. Furthermore, appropriate quality control (QC) measures must be established as analysis can be complicated by nuclear mtDNA segments (NUMTs), misalignment of homopolymer regions, sequencing errors, and other artefacts. Including such false variants in mtDNA haplotypes can lead to erroneous conclusions based on misinterpreted data.This thesis aimed to address the implementation challenges of mitogenome analysis and facilitate the transition to NGS in forensic laboratories. Paper I assessed the feasibility of generating forensic-quality mitogenome data from whole genome sequencing (WGS) data, which are valuable sources of mitogenome haplotypes for population studies. Due to NUMT interference, a 10% variant frequency threshold was necessary to produce haplotypes consistent with high-quality mitogenome datasets. Since length heteroplasmy (LHP) can also complicate mtDNA data analysis, Paper II characterized LHP in data generated on two NGS platforms as well as with Sanger-type sequencing. Different patterns of LHP were observed across sequencing technologies, further supporting current guidelines to ignore LHP in database searches and match comparisons in forensic analyses. Phylogenetic information can provide a valuable QC check of mtDNA data, identifying errors like artificial recombination and phantom mutations. Therefore, three haplogrouping tools were examined in Paper III, comparing their ability to predict an accurate haplogroup based on different mitogenome target ranges. The tools performed similarly, but EMPOP’s SAM2 algorithm produced more precise haplogroup predictions than the other two tools regardless of phylogeny or interpretation range. Building upon the previous three studies, Paper IV characterized 934 forensic-quality Swedish mitogenomes from a population genetics perspective. The complete mitogenome data demonstrated high haplotype diversity (0.9996) with a random match probability of 0.15%. In summary, these papers combine important insights to facilitate the application of mitogenome NGS analysis in forensic laboratories.
|
|
| 10. |
- Tehua Lu, Timothy, et al.
(författare)
-
An evaluation of the genetic-matched pair study design using genome-wide SNP data from the European population
- 2009
-
Ingår i: European Journal of Human Genetics. - : Springer Science and Business Media LLC. - 1018-4813 .- 1476-5438. ; 17:7, s. 967-975
-
Tidskriftsartikel (refereegranskat)abstract
- Genetic matching potentially provides a means to alleviate the effects of incomplete Mendelian randomization in population-based gene-disease association studies. We therefore evaluated the genetic-matched pair study design on the basis of genome-wide SNP data (309 790 markers; Affymetrix GeneChip Human Mapping 500K Array) from 2457 individuals, sampled at 23 different recruitment sites across Europe. Using pair-wise identity-by-state (IBS) as a matching criterion, we tried to derive a subset of markers that would allow identification of the best overall matching (BOM) partner for a given individual, based on the IBS status for the subset alone. However, our results suggest that, by following this approach, the prediction accuracy is only notably improved by the first 20 markers selected, and increases proportionally to the marker number thereafter. Furthermore, in a considerable proportion of cases (76.0%), the BOM of a given individual, based on the complete marker set, came from a different recruitment site than the individual itself. A second marker set, specifically selected for ancestry sensitivity using singular value decomposition, performed even more poorly and was no more capable of predicting the BOM than randomly chosen subsets. This leads us to conclude that, at least in Europe, the utility of the genetic-matched pair study design depends critically on the availability of comprehensive genotype information for both cases and controls. European Journal of Human Genetics (2009) 17, 967-975; doi:10.1038/ejhg.2008.266; published online 21 January 2009
|
|
