OK. I'll chime in here, seeing that I'm a specialist of human genetics and molecular biology. That comment would only make sense if 100% of australians attempted to become professional cyclists, don't confuse sport popularity with genetic selection. It's like saying an American can never be a top soccer player -it's just unlikely given the unpopularity of professional soccer in US and the anti-athletic population trends.

Any cycling coach at teen amateur levels will tell you you can only have so much coaching, training and determination to a certain level, beyond that, it's genetics. A good sports program needs to involve large numbers of selection -Russians did this for years.

There have been proven examples of exceptional atheletes having a known polymorphism, or genetic difference in a protein that gives them a significant advantage, and a larger than average proportion of that population has this polymorphism ( a famous finnish cross country skier has a heme protein with a higher affinity for oxygen).

Genetic makeup will affect base physical ability. It will also affect ability and utility of certain doping protocols, and this is very important in modern sports because performance modifying drugs are now the norm in almost all sports, especially cycling (a very long history in this). Some riders respond better to drugs than others. Any drug industry researcher will tell you that some drugs work significantly better/worse in different ethnic populations.

Sad truth, believe it or not,is that one can only get so good, even with doping. Determination is a factor, but at the sport's highest level, they are all determined.

Genetics is complex, and not due to any one factor, so you can't look at a son of Eddy Merckx, he doesn't have all Eddy's genes, only a clone of Eddy Merckx would have the genetics of Eddie Merckx.

So start cloning Lance.