bild

Coloured light micrograph of an IVF human embryo during pre- implantation genetic testing. The 8-celled embryo (near centre) produced by in vitro fertilisation (IVF) in the laboratory is being manipulated in order to have one of its cells removed. A pipette (at left) holds the embryo. At right a smaller pipette draws off one cell from the embryo after the embryo membrane has been punctured with acid. The cell is then genetically screened to check for disorders such as Down's syndrome. Once screened and found normal, this embryo will be implanted into the uterus (womb) wall. See photos M802/191- 195 for sequence of this procedure. (KEYSTONE/SCIENCE PHOTO LIBRARY/Pascal Goetgheluck)