Haploid Embryonic Stem Cells can be used in place of sperm for genetic modification

Researchers in Shanghai have developed a method that utilizes haploid stem cells for genetic modification rather than diploid stem cells.  Currently, diploid cells are used.  This leads to chimerism in the engineered mice.  This means the cells that form their bodies consist of two different genetic identities.  When the haploid cells are used, this does not occur which makes the desired genetic modifications more probable.[gallery]