From Embryonic Stem Cells, a Sperm Replacement and Easier Path to Genetic Modification

ScienceDaily (Apr. 26, 2012) — Researchers reporting in the April 27 issue of the journal Cell have devised a new and improved method for producing genetically modified animals for use in scientific research. The method relies on haploid embryonic stem cells (haESCs) instead of sperm to artificially fertilize immature egg cells. Such stem cells are similar to sperm in that they carry only genetic material from a mouse "dad."

Not only will the advance make it easier to produce genetically modified mice, but it may also enable genetic modification of animals that can't be modified by today's means. The technique might ultimately be used in assisted human reproduction for those affected by genetic disease, the researchers suggest.

"The current procedure to generate genetically modified animals is tedious and very inefficient," said Jinsong Li of the Shanghai Institute for Biological Sciences. "We thought if we can generate haploid embryonic stem cells and produce semicloned animals by simply injecting those cells into oocytes, we would be certain to get a transmission into offspring with limited breeding as half of the progeny will inherit the genetic modification."

Read on:  http://www.sciencedaily.com/releases/2012/04/120426135234.htm