Clones

Genetically identical organisms that arise from asexual reproduction

In nature there are many examples of clones, which are named after the Greek word for 'twig' or 'branch', e.g. protozoa such as bacteria and yeasts, which reproduce through duplication. Sponges propagate by constricting off parts of the organism, also known as budding. Many types of plants, such as strawberries or potatoes, propagate through side shoots, or runners, thereby cloning themselves.

Many plants are easy to clone since they possess the natural ability to regenerate from nearly all tissues, i.e. a complete plant can be grown from, for example, a piece of leaf, and will be genetically identical to it.

The first man-made cloned animal was generated already at the beginning of the last century. However, it was not until 1996, with the birth of the cloned sheep Dolly, that cloning attracted the public eye. Until then, clones were produced from embryonal stem cells, which still possess their original ability to develop (totipotency). Dolly was the first mammal to be cloned through a special technology (nuclear transfer) from an already differentiated adult cell.