DNAleftatacrimescenecouldbeusedinthefuturetobuildupapictureofanoffender’sfaceitwasrevealedtonight.AfirststeptowardsgeneticmugshotshasbeentakenbyresearchersintheUSwholinkspecificDNAmarkerswithfa

　　DNAleftatacrimescenecouldbeusedinthefuturetobuildupapictureofanoffender’sfaceitwasrevealedtonight.

　　AfirststeptowardsgeneticmugshotshasbeentakenbyresearchersintheUSwholinkspecificDNAmarkerswithfaceshape.Toidentifythegenestheyfocusedonknownmutations(突变)thatcausechangesofthefaceandhead.Normalversionsofthesegeneswerefoundtoinfluenceindividualfeatures. Forinstanceonegeneaffectedthelipsanothertheshapeandconfigurationofbonesaroundtheeyesandathirdtheappearanceofthemid-faceandskull.Intotal20geneshad“significanteffects”onfacialappearance.

　　LeadscientistProfessorMarkShriverfromPennsylvaniaStateUniversitysaid:“WeuseDNAtomatchtoanindividualoridentifyanindividualbutyoucangetsomuchmorefromDNA.Currentlywecan’tgofromDNAtoafaceorfromafacetoDNAbutitshouldbepossible.”Theimplicationsarefarreachingraisingthepossibilityofcreatingadatabankoffacialtypesbasedongeneticmarkers.DNAfromacrimescenecouldthenbeusedtoproducearoughimageofthefaceofanoffenderorvictim.Suchgeneticmugshotsmaybemorereliablethancomputer-generated“e-fits”basedonwitnesses’recollections.OtherusesofthetechniquemightincludeprovingtheidentityoffathersinpaternitycasesorvisualisingourremoteancestorsfromfossilDNA.

　　ThescientistswroteintheonlinejournalPublicLibraryofScienceGenetics:“Suchpredictivemodellingcouldbeforensicallyuseful;forexampleDNAleftatcrimescenescouldbetestedandfacespredictedinordertohelptonarrowthepoolofpotentialsuspects.Furtherourmethodscouldbeusedtopredictthefacialfeaturesofdescendantsdeceasedancestorsandevenextincthumanspecies.Inadditionthesemethodscouldprovetobeusefuldiagnostictools.”TheteamdevelopedamodelwhichfirstestablishedarangeofphysicalfaceshapesfrompeopleofmixedWestAfricanandEuropeanancestryfromtheUSBrazilandCapeVerde.Measurementsweretakenofthousandsofpointco-ordinatesongridsplacedover3Dimagesofthefaces.

　　Statisticalmethodswerethenusedtodeterminetherelationshipbetweenfacialdifferencesandtheeffectsofgenderethnicancestryandindividualgenevariants.

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