Professor Karim Nayernia and his team at New castle may have a break through. To grow human sperm from embryonic stem cells alone. The Synthetic sperm swims with head and tail, with some of the biological characteristics of real sperm. However, a change in the law would require, because the use of such in-vitro derived (IVD) sperm for reproduction was banned in Britain by the Human Fertilisation and Embryology Act last year.
From Times Online,
"Professor Nayernia said the IVD sperm have key traits of real sperm, including a haploid nucleus that has 23 chromosomes, instead of the 46 found in non-reproductive cells. “These cells are haploid, they have tails and a head, and they swim,” he said. “The only cells in the body that are like that are sperm.”"
This solved a millennium question of whether the chicken or the egg exist first. But science would only be possible if there is already a law exist in the nature.
'Synthetic sperm’ from stem cells raises hope for male infertility