Writing in The Lancet medical journal, they suggested same-sex transplants should be considered in future. However, the UK Transplant Authority said its own research had not found any gender difference. The idea of the "sex" of donor tissue influencing how it is received by the recipient's immune system is not a new one. In stem-cell transplants, men who get cells from a female are at an increased risk of dangerous "graft-versus-host" disease, and women who get "male" cells are more likely to reject them, or have an immune reaction to molecules specific to males found on the surface of cells. The researchers from the University Hospital in Basel examined the outcome of a total of 195,516 transplants between 1985 and 2004 at more than 400 hospitals in Europe. They found that "graft loss" - the rejection of the new organ - was more likely in kidneys from female donors than those from male donors after both a year and 10 years. Read more at: http://news.bbc.co.uk/1/hi/health/7489539.stm