<code id='A8038F381D'></code><style id='A8038F381D'></style>
      • <acronym id='A8038F381D'></acronym>
      <center id='A8038F381D'><center id='A8038F381D'><tfoot id='A8038F381D'></tfoot></center><abbr id='A8038F381D'><dir id='A8038F381D'><tfoot id='A8038F381D'></tfoot><noframes id='A8038F381D'>
      • <optgroup id='A8038F381D'><strike id='A8038F381D'><sup id='A8038F381D'></sup></strike><code id='A8038F381D'></code></optgroup>
        5. <b id='A8038F381D'><label id='A8038F381D'><select id='A8038F381D'><dt id='A8038F381D'><span id='A8038F381D'></span></dt></select></label></b><u id='A8038F381D'></u>
          <i id='A8038F381D'><strike id='A8038F381D'><tt id='A8038F381D'><pre id='A8038F381D'></pre></tt></strike></i>
           


   

   

   
   
   
   
   
   
   
   
   
   
   
   
   

   
   
   
   
   
   
   
  
           
  
           
  
           
   
           
    
           
     
           
      
           
       
      
           
      
           
       
           
        
           
         
           
           
          
           
         
           
         
           
           
          
           
         
           
          
        
           
       
           
       
           
        
           
        
           
        
           
        
           
       
           
      
           
       
      
           
      
           
       
           
       
           
       
           
       
           
        
           
        
          
          00:00 
        
           
       
           
       
           
      
           
      
           
        
        
        
       
           
        00:00 
         
        00:00 
        LIVE 
       
           
        
       
           
        
           
        
           
        
           
        
           
       
           
       
           
       
           
        
        
        
        
        
        
        
        
        
      
           
       
    
    
      
           
       
           
      
           
     
           
     
           
       
     
           
     
           
      
           
      
           
      
           
      
           
       
           
      
           
      
           
      
           
       
           
       
          
         buffering 
       
           
      
           
      
           
       
           
        
           
        
          
          Replay 
        
           
       
           
      
           
       
      
           
      
           
       
           
       
           
        
           
        
           
        
           
       
           
      
           
      
           
      
           
      
           
      
           
       
           
      
           
     
           
     
           
      
           
     
           
     
           
      
           
       
           
        
           
       
           
       
           
        
          
          LIVE 
        
           
        00:00 
         /  
        00:00 
       
           
       
           
        
           
        
           
        
           
         
           
         
           
         
           
         
           
         
           
         
           
        
           
        
           
        
           
       
           
       
           
        
           
        
          
          LIVE 
        
           
       
           
       
           
        
           
        
          
          CC 
        
           
       
           
       
           
        
           
       
           
       
           
       
           
        
           
        
           
         
           
        
           
       
           
       
           
        
           
       
           
      
           
      
           
       
           
        
           
        
           
         
           
         
           
         
           
          
           
          
           
          
           
         
           
        
           
       
           
      
           
      
           
       
           
     
       
           
    
       
           
       
    
  
       
           
   
       
           
       
       
           
      
           
      
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       
           
       Opacity : 
        
      
           
     
           
     
           
     
           
      
           
  
     
           
    
           
    
           
    
           
     
          
       Share: 
     
           
      
     
           
      
      Copy 
     
           
      
    
           
    
          
      Close 
      
    
           
    
           
      
    
           
    
           
   
           
  
           
  
           
    
    
    
   
           
   
           
 
    
   
           
   
           
   
           
    
           
     
           
      
           
       
           
        
           
          
          
         
          
          hotspot 

          
          
            
          
          

           
           
        
           
       
           
      
           
     
           
    
           
    
           
     
           
      
           
      
           

                       
          knowledge  
          
                                   
                 
                                      author：explore   
                                        
                                      
                                      -
 
browse：8249
                                  
                                    
          
                                    
            
          
 
          Dolly sheep
          Alex Hogan/STAT, Getty Images
          Dolly, the first animal to be cloned from an adult of its species, was born 20 years ago today at the Roslin Institute in Scotland. When her creators announced what they had done, it triggered warnings of rich people cloning themselves for spare parts, of tyrants cloning soldiers for armies, of bereaved parents cloning their dead child to produce a replacement — and promises that the technique would bring medical breakthroughs. Which raises some questions:
          Why are there no human clones?
          Because of scientific, ethical, and commercial reasons.
          advertisement
          The scientists who created Dolly — named after Dolly Parton, naturally — removed the DNA from a sheep ovum, fused the ovum with a mammary epithelial cell from an adult “donor” sheep, and transplanted the result, now carrying DNA only from the donor, into a surrogate ewe. But that technique, called somatic cell nuclear transfer (SCNT), turned out not to be so easy in other species.
          Get unlimited access to award-winning journalism and exclusive events.					
          Subscribe													Log In											
           
 
 
          

                              
          
                                 Previous article：

                                
                                          Biden outlines 'new path' to provide student loan relief after Supreme Court rejection
                                
                            
          Next article：  
                                      
                                          Why palliative psychiatry is worth discussing
                                                                    
          

      
           
      
           
        
           
                                               
        
           focus 
           
                   
      
           
  
  
          
    
          
        
          
            
          
                                                     
                
          Wikipedia
          
                            
          
        
          
        
    
          

          

    

      
           
     
           


   
    
           
   
           
  
 

  
           
    
           
           
           
            
            Back To Top 
           
           
           
           

            
           
                                                                    
                 
          focus
           
                                      
            
           
          
           
                                                          
             
          explore
           
                             
            
           
            
           

                                                         
             
          entertainment
           
               
              
            
           
            
           
                                                         
             
          Wikipedia
           
                             
      
           
 
     
           
     
           
      
          
              AdobeAsdrugmakersracetojointheobesitydrugmarketignitedbytheapprovalofWegovyandZepbound,they’renotjus
             
           
      
          
        © 2013-2023.Company name All rights reserved.Site Map 
         WSS-More Templates  
             Guangdong ICP34name