CLONING

The word clone comes from the Greek word " Klon meaning "twing". It refers to a group of genetically identical cells or tissues or organisms. The cloning of plants and animals was first attempted eighty years ago (during 1950s) and since then many plants viz. potato, carrot, sugarcane, mango, citurs, roses, grasses, etc and few animals, particularly lower animals, have been cloned because they commonly reproduce asexually.

  Among the higher animals, clones are not found naturally and artificial attempts have not been very successful. Such experiments ere conducted on frogs by Robert Briggs and Thomas King in 1950s and by john Gurdon in 1970s and who reported that the transplanted nucleus was often able to support normal development of the egg into a tadpole. But, such experiments were far and few.

Until in 1997, when a Scottish group of researchers shook the world by storm, announcing the birth of "Dolly", a lamb cloned from a differentiated cell. Later in 2003, at age of six, however, Dolly suffered from a lung disease and died. since then scientists have cloned numerous other mammals' viz. mice and dogs.

  The successful cloning of numerous mammals raised hopes of cloning of humans too!although, it also ignited unprecedented ethical issues. The controversial experiments on human cloning were carried out by several labs around the world. In 2001, a research group in Massachusetts observed a few early cell divisions in such as experiment . A few years later, South Korean researches reported cloning embryos to an early stage called the blastocyst stage. 

Although the heated debate about in relevance still rages but research is also going on in this direction . Who knows one day we might have Sachin Tendulkar or Anna Hazare or A.P.J Abdul Kalam or even Osama Bin Laden!