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dc.contributor.advisorKirstin, Janssen
dc.contributor.authorSalvo, Nina Mjølsnes
dc.date.accessioned2024-06-14T07:34:06Z
dc.date.available2024-06-14T07:34:06Z
dc.date.issued2024-06-27
dc.description.abstractForensic DNA phenotyping (FDP) can aid police investigations where there is no match between the crime scene DNA and a suspect or a database hit. By using FDP, we can predict appearance and biogeographical ancestry (BGA) of an unknown person. These DNA tests are currently being implemented in forensic casework in many countries. However, prior to implementation, the methods have to be evaluated and validated. The focus of this thesis was to evaluate existing genotyping methods and tools for prediction of eye colour, hair colour and BGA. Based on the limitations found, we further investigated the genetics of eye colour. The ForenSeqTM DNA Signature Prep kit on a MiSeq FGx system were used to genotype ancestry- and phenotype-informative SNPs in a Norwegian study population (n=756). The HIrisPlex web tool were used to predict eye and hair colour, and the Universal Analysis Software (UAS), FROG-kb and GenoGeographer were used to infer BGA. With some adjustments for the analysis criteria, we demonstrated that the ForenSeq was a reliable and sensitive genotyping system. Blue and brown eye colour, red and black hair colour and BGA on a continental scale could be predicted with high accuracies. This is highly useful for the police to narrow down a pool of potential suspects. Interestingly, we observed lower prediction accuracy for blue eye colour in the Norwegian study population than reported in other European populations. Furthermore, we revealed some rare genotype-phenotype associations for eye colour. By developing new prediction models, we were able to increase the number of correct predictions for the blue-eyed individuals. We further investigated the genetics of eye colour by sequencing the OCA2-HERC2 locus in 94 blue-or brown-eyed individuals and identified new genetic variants that were associated with blue eye colour. Inclusion of these variants in future models might increase the prediction accuracy.en_US
dc.description.abstractDNA fenotyping er prediksjon av fysiske trekk og biogeografisk opphav fra DNA. Dette kan være relevant i politietterforskning hvor et spor har ført til en DNA profil, men hvor det ikke er funnet et treff med DNA-profiler fra en mistenkt eller i politiets DNA-register. Utvidede gentester som fenotyping kan i disse sakene predikere egenskaper til en ukjent person, som kan hjelpe politiet å redusere søket etter en mulig gjerningsmann, og dermed øke presisjonen i arbeidet. Disse testene er i implementeringsfasen i mange land. Før testene kan tas i bruk må de evalueres og valideres nøye. Fokus for denne avhandlingen var å evaluere en eksisterende sekvenseringsmetode for genotyping av spesifikke genetiske markører og verktøy for predikering av øyenfarge, hårfarge og biogeografisk opphav. Basert på funnene i disse studiene, utførte vi nye undersøkelser for å finne nye sammenhenger mellom genene og øyenfarge. Vi brukte ForenSeqTM DNA Signature Prep kit og en MiSeq FGx sekvenseringsplatform for å genotype spesifikke SNP markører i en norsk studiepopulasjon på 756 individer. Prediksjonsverktøyet, HIrisPlex, ble brukt til å predikere øyenfarge og hårfarge, og Universal Analysis Software (UAS), FROG-kb og GenoGeographer ble brukt til å predikere biogeografisk opphav. Med noen justeringer av analysekriteriene, viste vi at ForenSeq var et pålitelig og sensitivt genotyping-system. Blå og brun øyenfarge, rødt og svart hår, og biogeografisk opphav i kontinentale grupper ble predikert med høy nøyaktighet. Høyst interessant så observerte vi en lavere nøyaktighet for blå øyne i den norske studiepopulasjonen enn hva som er rapportert ellers i Europa. Vi observerte også unike genotype-fenotype assosiasjoner for øyenfarge. Basert på dette og andre studier fra Skandinavia, utviklet vi nye prediksjonsmodeller som økte antall korrekte prediksjoner for personer med blå øyne. I tillegg sekvenserte vi OCA2-HERC2 regionen i disse individene og fant nye genetiske markører som har potensialet til å øke prediksjonsnøyaktigheten ytterligere.en_US
dc.description.doctoraltypeph.d.en_US
dc.description.popularabstractOur DNA store information about appearance such as eye colour, hair colour, skin colour, body height and facial structures. This can be valuable information for the police in criminal investigations where a DNA profile is obtained from the crime scene, but there is no match with a suspect or a database hit. The focus for this thesis was to evaluate and improve extended DNA tests for police investigations that can give us hints about what an unknown person might look like, similar to an eyewitness. By investigating the DNA from over 750 volunteers in Norway we found that current DNA tests accurately predicts blue and brown eye colour, red and black hair colour, and ancestry on a continental level. Interestingly, more individuals in Norway have blue eye colour than what the tests predicts. We therefore investigated the genes of these individuals and found new connections between the genes and eye colour, which can be used in future DNA tests to increase the accuracy in Scandinavia.en_US
dc.description.sponsorshipUiT - The Arctic University of Norwayen_US
dc.identifier.urihttps://hdl.handle.net/10037/33807
dc.language.isoengen_US
dc.publisherUiT The Arctic University of Norwayen_US
dc.publisherUiT Norges arktiske universiteten_US
dc.relation.haspart<p>Paper 1: Salvo, N.M., Janssen, K., Kirsebom, M.K., Meyer, O.S., Berg, T. & Olsen G.-H. (2021). Predicting eye and hair colour in a Norwegian population using Verogen’s ForenSeq<sup>TM</sup> DNA signature prep kit. <i>Forensic Science International: Genetics, 56</i>, 102620. Also available in Munin at <a href=https://hdl.handle.net/10037/26434>https://hdl.handle.net/10037/26434</a>. <p>Paper 2: Salvo, N.M., Olsen, G.-H., Berg, T. & Janssen K. Biogeographical ancestry analyses using the ForenSeq<sup>TM</sup> DNA Signature Prep kit and multiple prediction tools. (Submitted manuscript). Now published in <i>Genes, 2024, 15</i>(4), 510, available in Munin at <a href=https://hdl.handle.net/10037/33806>https://hdl.handle.net/10037/33806</a>. <p>Paper 3: Meyer, O.S., Salvo, N.M., Kjærbye, A., Kjersem, M., Andersen, M., Sørensen, E., … Andersen, J.D. (2021). Prediction of Eye Colour in Scandinavians Using the EyeColour 11 (EC11) SNP Set. <i>Genes, 12</i>(6), 821. Also available in Munin at <a href=https://hdl.handle.net/10037/23107>https://hdl.handle.net/10037/23107</a>. <p>Paper 4: Salvo, N.M., Mathisen, M.G., Janssen, K., Berg, T. & Olsen, G.-H. (2022). Experimental long-distance haplotyping of <i>OCA2-HERC2</i> variants. <i>Forensic Science International: Genetics Supplement Series, 8</i>, 188-190. Also available in Munin at <a href=https://hdl.handle.net/10037/28229>https://hdl.handle.net/10037/28229</a>. <p>Paper 5: Salvo, N.M., Andersen, J.D., Janssen, K., Meyer, O.L., Berg, T., Børsting, C. & Olsen, G.-H. (2023). Association between Variants in the <i>OCA2-HERC2</i> Region and Blue Eye Colour in <i>HERC2</i> rs12913832 AA and AG Individuals. <i>Genes, 14</i>(3), 698. Also available in Munin at <a href=https://hdl.handle.net/10037/30070>https://hdl.handle.net/10037/30070</a>. <p>Paper 6: Salvo, N.M., Janssen, K., Olsen, G.-H., Berg, T. & Andersen, J.D. (2022). Association between copy number variations in the <i>OCA2-HERC2</i> locus and human eye colour. <i>Forensic Science International: Genetics Supplement Series, 8</i>, 82–84. Also available at <a href=https://doi.org/10.1016/j.fsigss.2022.09.030>https://doi.org/10.1016/j.fsigss.2022.09.030</a>.en_US
dc.rights.accessRightsopenAccessen_US
dc.rights.holderCopyright 2024 The Author(s)
dc.subject.courseIDDOKTOR-003
dc.subjectForensic geneticsen_US
dc.subjectDNA phenotypingen_US
dc.subjectMassively parallel sequencingen_US
dc.titleForensic DNA phenotyping - Towards reliable and accurate DNA tests for prediction of eye colour, hair colour and biogeographical ancestryen_US
dc.typeDoctoral thesisen_US
dc.typeDoktorgradsavhandlingen_US


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