Why do I wake 4 hours after going to sleep?

Michael Hastings - Short sleeper I guess. We're trying to find out, we and other people, to discovered the genes. Obviously, one approach is mainly using mice as your experimental model and zebrafish as well. We need to find the genes behind this because it's a common feature of people from individual to individual, to have different lengths of sleep, just the same as people have got different eye colour and height. But we know very little about the genes that control the length of sleep as opposed to the genes that control the timing of sleep.