Skip to navigation | Skip to content  Stem cells can grow into
sperm   Mouse sperm cell (LBNL).  Stem cells can be coaxed into
forming sperm that can potentially fertilise eggs, according to
U.S. research.  Dr George Daley, from the Children's Hospital in
Boston, Massachusetts and reported the results today online in
the journal Nature.  The researchers took germ cells from the
part of the mouse embryo that forms egg and sperm cells.  They
cultured the cells for a week in a dish of retinoic acid. This
caused them to multiply and form embryoid bodies, spheres that
can contain a mix of versatile cells.  The researchers then
extracted the sperm from the embryoid bodies and injected them
into unfertilised mouse eggs.  These developed into a typical
cluster of early embryonic cells called blastocysts. Each gamete
contributed a set of chromosomes to provide a full complement of
genes.  The researchers have yet to take their work further to
see if the technique can give birth to live young.  "What we
would really li