"That is a dramatic change from a few years ago, when it was seen as a $3-$5 billion, 15- to 25-year programme."
Rapid progress would continue, he said.
The project to sequence the genes of up to 50 people is part of a year-long, $US75 million ($180 million) programme announced last week by Celera and its parent company, Applera, to develop medical drugs and genetic tests using Celera's genetic database.
Dr Venter said that knowing the minor variations between people's genes could help to explain the cause of disease.
Understanding each person's genetic structure would revolutionise medicine, he said.
"We can understand people's metabolism much better by understanding the genetic code. It must have a dramatic impact on what diet one should have."
Gene mapping would also mean that doctors could avoid giving particular medicines to people whose genetic structures made them more liable to react against those drugs.
But he cautioned against seeing the new technology as providing absolute certainty about whether any drug would work.
"The fact that we only found 26,000 genes in the human genome helps demonstrate the fact that most of you, or myself, are alive because of genetic determinism, and that the genome in your gene code does not determine exactly who you are in any exact form."
He said new biotechnology discoveries could greatly reduce the need to burn fossil fuels, and so cut greenhouse gas emissions.
"We have found organisms from the bottom of hyper-vents in the Pacific that take carbon dioxide as energy and convert it to methane which can be used as a fuel," he said.
"Other microbes can split water and create hydrogen gas, which can obviously be used as a fuel."
Dr Venter is a controversial figure because he formed Celera to effectively compete with the publicly funded human genome project, and aims to make money from patenting his discoveries.
He told one questioner that patents actually encouraged scientists to make their discoveries public, rather than maintaining trade secrecy. Patents had to be published so that their inventors could charge royalties.
He said the key factor in Celera's success in cracking the human genetic code first was that it raised $US350 million from Applera - far more than any public body could afford.
Dr Venter spoke fondly of New Zealand, which he visited in February to buy a 29m sloop built by Glenfield's Cookson Boats, which has also just sold racing yachts to the kings of Spain and Norway.
"The science talent in New Zealand is equal to the science talent that I have seen anywhere else," he said.
"If anything is lacking there, it's the investment climate ... to take things further."
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