knowledge -WSS

knowledge

author：knowledge 2025-10-01 22:59:55 - browse：3719

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.

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： Continuity nursing helped my family in our darkest PICU moments
Next article： Did the public have the right to know Arthur Ashe had AIDS?

WSS

Make 'food is medicine' a key part of White House nutrition meeting

Gut bacteria may contribute to kidney autoimmunity, study finds

Hundreds died while taking an arthritis drug, but nobody alerted patients

Drug companies' payments and gifts affect physicians' prescribing

Harvard scientists, with Google, unveil the most detailed brain map ever

Oral obesity drug from Viking Therapeutics hits key early target

explore

knowledge

Why are there no human clones?

Wikipedia

Biden outlines 'new path' to provide student loan relief after Supreme Court rejection

Overprescribed: High cost isn't America's only drug problem

Over 800 arrested across France in 3rd night of riots after fatal police shooting of teen

Pfizer's Covid pill remains 89% effective in final analysis, company says

Medical leaders decry Supreme Court decision on affirmative action

Inside the fall of star MIT scientist David Sabatini

Medicare proposal to cover medical devices draws a mixed reaction

Australia's humpback populations rebound raising hopes of marine scientists

Alkermes shareholders re

Four alarming medical procedures we’re glad history forgot

leisure time

Inside the fall of star MIT scientist David Sabatini

When is a doctor not a doctor? Try when patients address women doctors

Scientists uncover potential path to treating deadly childhood tumor

Drug companies' payments and gifts affect physicians' prescribing

Bacterial infection may be ‘key event’ in endometriosis, study says

Grail is spending more than ever lobbying Congress

Wikipedia

Wikipedia

entertainment

focus