I am surprised by the ignorance and prejudice displayed by the commentators regarding this article. Some just have to bring the God debate into it, usually without having any understanding of the facts, others seem to think that if it exists in nature there is a reason!\n\nGod and evolution are not mutually exclusive - many scientists find their work supports their faith - surely the first prerequisite is to have an open mind? Could all real scientists please stop jumping on this bandwagon and allow freedom of opinion? Using God as a perpetual scapegoat for anything that is wrong in the world of science is just plain puerile.\n\nSecondly, many things exist in nature that are deleterious - nature also generally weeds them out within a few generations, unless they also offer advantages in changing situations. For example, cystic fibrosis is a horrible condition, which in milder forms offers protection against cholera. Nature does not individuals to be perfect, rather the population as a whole needs to have the characteristics necessary for survival, and this means variation. Some of which will work, and some of which will not, according to the changing conditions.\n\nCan we please vote for common sense, tolerance and INFORMED debate?