Japanese researchers have succeeded in breeding a sow with human genes that has passed them on to her piglets, a report by Kyodo News agency said on Friday. The Osaka University team led by organ transplant specialist Ryota Shirakura believed the programme could one day lead to animals providing donor organs for humans with less risk of rejection, it said. The scientists injected 362 pigs' ova with the human gene DAF, Kyodo said, resulting in the births of 51 piglets.