WhyClone? 　　Researchadvancesoverthepastdecadehavetoldusthat,withalittlework,wehumanscanclonejustaboutanythingwewant,fromfrogstomonkeysandprobablyevenourselves! 　　So,wecanclonethings,butwhywouldwewantto?Let'slookatsomeofthereasonspeoplegivetojustifycloning. 　　1.Cloningformedicalpurposes 　　Cloningformedicalpurposes 　　Ofallthereasons,cloningformedicalpurposeshasthemostpotentialtobenefitlargenumbersofpeople.Howmightcloningbeusedinmedicine? 　　*Cloninganimalmodelsofdisease 　　Muchofwhatresearcherslearnabouthumandiseasecomesfromstudyinganimalmodelssuchasmice.Often,animalmodelsaregeneticallyengineeredtocarrydisease-causingmutationsintheirgenes.Creatingthesetransgenicanimalsisatime-intensiveprocessthatrequirestrial-and-errorandseveralgenerationsofbreeding.Cloningtechnologiesmightreducethetimeneededtomakeatransgenicanimalmodel,andtheresultwouldbeapopulationofgeneticallyidenticalanimalsforstudy. 　　*Cloningstemcellsforresearch 　　Stemcellsarethebody'sbuildingblocks,responsiblefordeveloping,maintainingandrepairingthebodythroughoutlife.Asaresult,theymightbeusedtorepairdamagedordiseasedorgansandtissues.Researchersarecurrentlylookingtowardcloningasawaytocreategeneticallydefinedhumanstemcellsforresearchandmedicalpurposes. 　　*"Pharming"fordrugproduction 　　Farmanimalssuchascows,sheepandgoatsarecurrentlybeinggeneticallyengineeredtoproducedrugsorproteinsthatareusefulinmedicine.Justlikecreatinganimalmodelsofdisease,cloningmightbeafasterwaytoproducelargeherdsofgeneticallyengineeredanimals. 　　2.RevivingEndangeredorExtinctSpecies 　　Dinosaur 　　HaveyouseenJurassicPark?Inthisfeaturefilm,scientistsuseDNApreservedfortensofmillionsofyearstoclonedinosaurs.Theyfindtrouble,however,whentheyrealizethattheclonedcreaturesaresmarterandfiercerthanexpected. 　　Couldwereallyclonedinosaurs? 　　Intheory?Yes.Whatwouldyouneedtodothis? 　　*Awell-preservedsourceofDNAfromtheextinctdinosaur,and 　　*Acloselyrelatedspecies,currentlyliving,thatcouldserveasasurrogatemother 　　Inreality?Probablynot.It'snotlikelythatdinosaurDNAcouldsurviveundamagedforsuchalongtime.However,scientistshavetriedtoclonespeciesthatbecameextinctmorerecently,usingDNAfromwell-preservedtissuesamples. 　　3.ReproducingaDeceasedPet 　　Pet 　　Nojoke!Ifyoureallywantedto,andifyouhadenoughmoney,youcouldcloneyourbelovedfamilycat.AtleastonebiotechnologycompanyintheUnitedStatesofferscatcloningservicesfortheprivilegedandbereaved,andtheyarenowworkingtoclonedogs.Butdon'tassumethatyourclonedkittywillbeexactlythesameastheoneyouknowandlove. 　　4.CloningHumans? 　　Newborn 　　Tocloneornottoclone:thatisthequestion.Theprospectofcloninghumansishighlycontroversialandraisesanumberofethical,legalandsocialchallengesthatneedtobeconsidered. 　　Whywouldanyonewanttoclonehumans?Somereasonsinclude: 　　*Tohelpinfertilecoupleshavechildren 　　*Toreplaceadeceasedchild 　　---