I already responded to this.
Then tell me how many beneficial mutations you can point to that was fixated in our population ? Right now the harmful mutations have resulted into over 6,000 genetic disorders.
I can think of two. Sicklemia for those in certain environments where it is beneficial (african americans in environments containing malaria). Although this one is a double edged sword, as it poses the potential for sickle cell anemia, it does confer an advantage in fending off the disease in that environment. Don't try and tell me this isn't at all adaptive. It may not be the best example, but it does demonstrate that which you asked about. Within that environment, this would be an advantage and lead to greater survivability. Out of that environment, it is simply a burden.
A better example is the mutation that europeans underwent at around 5,000 B.C. which allowed to them digest lactase past infancy and into adulthood, and which many of us possess today. This was a result of having had domesticated animals the last 6,000 years before that (since 11,000 BC), which is the only reason we were drinking mammalian baby food from another species. As hunter-gathers, before animal domestication and the advent of agriculture (the two things which allowed us to settle down in one place and start civilization), this simply would not have happened. It is not natural for us or any species to drink what is essentially baby-food past the time when we are babies. Being "lactose intolerant" is actually the normal state for most mammals as adults. It is this mutation that allows those of european decent to metabolize lactase without issue. Therefore, it could be argued, that they could glean a larger amount of nutrients from their diet throughout their lifespan, and added another food source for them, which they could control through domestication. This would have conferred a great survival advantage, allowed them to lead longer, healthier lives, and to feed more people, creating more chance for procreation, thus passing on the mutation, which we now experience as the ability to digest lactose.
(Being a vegan, I am vehemently opposed to dairy consumption, because of the unethical nature inherent in the production process of factory farming (check out
Earthlings.com | A Film by Nation Earth for the inside scoop). I ask anyone open to learning about where there food comes from to go to that website and watch the movie. Please!)