http://news.bbc.co.uk/1/hi/health/7167892.stm Granted this is a first reaction without much thought but...
Apparently the gene that causes Down's syndrom may actually help prevent cancereous tumours. So researchers now want to explore the posibility of using this to help treat/prevent said tumours... This might just be me but, a person who does not have cancer but still has Down's syndrome is in fact not without a major problem and thus makes me ask "wtf are they thinking!?"