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1、Theworldwasstunnedbythenewsinthesummerof1995,whenaBritishembryologistnamedIanWilmut,andhisresearchteam,successfullyclonedDollythesheepusingthetechniqueofnucleartransfer.ReplacingtheDNAofonesheep’seggwiththeDNAofanothersheep’stheteamcreatedDolly.Plantsandlowerformsofanimallif
2、ehavebeensuccessfullyclonedformanyyears,butbeforeWilmut’sannouncement,ithadbeenthoughtbymanytobeunlikelythatsuchaprocedurecouldbeperformedonlargermammalsandlifeforms.Theworldmediawasimmediatelyfilledwithheateddiscussionsabouttheethicalimplicationsofcloning. Someofthemostpow
3、erfulpeopleintheworldhavefeltcompelledtoactagainstthisthreat.PresidentClintonswiftlyimposedabanonfederalfundingforhuman-cloningresearch.BillswereputintheworksinbothhousesofCongresstooutlawhumancloningbecauseitwasdeemedasafundamentallyevilthingthatmustbestopped.Butwhat,exactl
4、y,isbadaboutit?Fromanethicalpointofview,itisdifficulttoseeexactlywhatiswrongwithcloninghumanbeings.Thepeoplewhoareafraidofcloningtendtoassumethatsomeonewould,forexample,breakintoNapoleon’sTomb,stealsomeDNAandmakeabunchofemperors.Inreality,infertilepeoplewhousedonatedsperm,eg
5、gs,orembryoswouldprobablyusecloning.Dothepotentialharmsoutweighthebenefitsofcloning?Fromwhatweknownow,theydon’t.Therefore,weshouldnotrushplacingabanonapotentiallyusefulmethodofhelpinginfertile,geneticallyat-risk,homosexual,orsinglepeopletobecomeparents. Dohumanbeingshaveari
6、ghttoreproduce?Noonehasthemoralrighttotellanotherpersonthattheyshouldnotbeabletohavechildren,andIdon’tseewhyBillClintonhasthatrighteither.Ifhumanshavearighttoreproduce,whatrightdoessocietyhavetolimitthemeans?Essentiallyallreproductiondonethesedaysiswithmedicalhelpatdelivery,
7、andevenbefore.Trulynaturalhumanreproductionwouldmakepregnancy-relateddeaththenumberonekillerofadultwomen. Someformsofmedicalhelparemoreinvasivethanothers.Within-vitrofertilization,thespermandeggarecombinedinalabandsurgicallyimplantedinthewomb.Lessthantwodecadesago,asimilarc
8、oncernwasraisedovertheethicalissuesinvolving"test-tubebabies".Today,nearly3
