An Irish study suggests diabetes can damage DNA in men's sperm, thereby affecting fertility.
In the first study to compare the quality of DNA in sperm from diabetic and non-diabetic men, researchers at Queen's University in Belfast, Northern Ireland, discovered DNA in the nuclei of the sperm cells had greater levels of fragmentation in diabetic men -- 52 percent versus 32 percent in non-diabetic men -- and that there were more deletions of DNA in the tiny, energy-generating structures in the cells called mitochondria.
Ishola Agbaje, who led the study, said: "If the increasing trend in the incidence of type I diabetes continues, this will result in a 50 percent increase over the next 10 years. As a consequence, diabetes will affect many more men prior to and during their reproductive years."
Professor Sheena Lewis, scientific director of the university's Reproductive Medicine Research Group, cautioned it was still unclear whether the DNA damage caused by diabetes would have the same effect on men's fertility and the health of future children as DNA damage caused by other factors, such as smoking.
The study is available online in the journal Human Reproduction


Sperm Activates Egg By New Protein
Canadian researchers have discovered a new protein involved in the fertilization of an egg by sperm.
The discovery by Richard Oko and colleagues at Queen's University in Kingston, Ontario, might lead to new reproductive technologies and better understanding of reproductive disorders.
When the sperm head and egg start fusing and create an opening between them, the sperm cell releases proteins through the opening that activate the egg, said Oko.
That allows the sperm cell to further enter the egg and mix its material with that of the egg, thus creating one cell -- the zygote. The egg activation steps are well known, but it is not yet clear which molecules initiate the activation process.
The study identifies a protein that appears to play a key role in the first stages of egg activation. The researchers isolated the protein, called postacrosomal sheath WW domain-binding protein, or PAWP, and found without PAWP, sperm cells were