第十四篇：
Acontroversyeruptedinthescientificcommunityinearly 1998 overtheuseofDNAfingerprintingincriminalinvestigations. DNAfingerprintingwasintroducedin 1987 asamethodtoidentifyindividualsbasedonapatternseenintheirDNA, themoleculeofwhichgenesaremade. DNAispresentineverycellofthebodyexceptredbloodcells. DNAfingerprintinghasbeenusedsuccessfullyinvariousways, suchastodeterminepaternitywhereitisnotclearwhothefatherofaparticularchildis. However, itisintheareaofcriminalinvestigationsthatDNAfingerprintinghaspotentiallypowerfulandcontroversialuses.
DNAfingerprintingandotherDNAanalysistechniqueshaverevolutionizedcriminalinvestigationsbygivinginvestigatorspowerfulnewtoolsintheattempttotroveguilt, notjustestablishinnocence. Whenusedincriminalinvestigations, aDNAfingerprintpatternfromasuspectiscomparedwithaDNAfingerprintpatternobtainedfromsuchmaterialashairsorbloodfoundatthesceneofacrime. AmatchbetweenthetwoDNAsamplescanbeusedasevidencetoconvictasuspect.
Thecontroversyin 1998 stemmedformareportpublishedinDecember 1991 bypopulationgeneticistsRichardC. LewontinofHarvardUniversityinCambridge, Mass., andDanielL. HartlcalledintoquestionthemethodstocalculatehowlikelyitisthatamatchbetweentwoDNAfingerprintsmightoccurbychancealone. Inparticular, theyarguedthatthecurrentmethodcannotproperlydeterminethelikelihoodthattwoDNAsampleswillmatchbecausetheycamefromthesameindividualratherthansimplyfromtwodifferentindividualswhoaremembersofthesameethnicgroup. LewontinandHartlcalledforbettersurveysofDNApatternsmethodsareadequate.
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