What are the problems with selective breeding? 10 points winning answer?
Genetic pleiotropy — when selecting for one thing, you may inadvertantly be selecting for something else. One gene may have multiple functions, only some of which might be desirable. Another possibility is incidental selection for linked traits. Read up a bit on high uric acid production in Dalmations. Basically, the spotted coat gene sits nice and close to the gene for high uric acid. So we accidentally selected all Dalmations with high uric acid production. Another problem is — people are stupid. They like to intentionally select for characteristics which directly cause serious abnormalities. Pugs who can’t breath (we squished their noses), shar peis with skin problems, horses with HYPP, beligian blue cattle, bully whippets, German Shepards with hip problems etc, etc. People have a bad track record for selecting things that aren’t in the best intests of health of the animal, but should be pretty obvious to people who take even a minute to think about them. Finally, we have issues
