LONDON (Reuters) - Britain said Wednesday it would end anonymity for sperm and egg donors next year in an move that a fertility expert said could worsen the country's already critical shortage of donations. Children conceived from donated eggs or sperm will have the right to track down their biological parents from the age of 18, public health minister Melanie Johnson told a news conference. "I firmly believe donor-conceived people have a right to information about their genetic origins that is currently denied them, including the identity of their donor," she said. "Today's new regulations will...remove the major discrepancy that...