Understanding how a relatively small number of genes translate into the incredible complexity of a human being will be one of the challenges of the future. "We now have the list of parts of the human body," said Sir John Sulston, who spearheaded UK efforts to crack the human code. "Now we have to find out what all the parts are, we have to find out how all the parts interact and we have to probably do some very sophisticated things to understand how the control of those interactions goes forward to actually build our bodies. "
Researchers are predicting that the data will unlock some of the secrets of how genes influence behavior. But they warn against headline-making claims that a given gene can be the cause of crime, homosexuality or even sporting brilliance. Dr. Craig Venter, the leader of the private effort to decode the human genome, said genetic determinism, the idea that a person is controlled by their genes, was a fallacy. "There are two fallacies to be avoided," Dr. Venter's team write in the journal Science. "Determinism, the idea that all characteristics of a person are ' hard-wired' by the genome; and reductionism, that now the human sequence is completely known, it is just a matter of time before our understanding of gene functions and interactions will provide a complete causal description of human variability. "
One implication of the work, said Dr. Venter, was to calm fears about human cloning. "Trying to clone a person to gain immortality would be a pointless venture," he said. "This whole debate about cloning is much ado about nothing because while you may be able to, as with twins, have someone who looks similar to you, the chances of them having the same personality and the same outcome in life is close to zero. That's why you can't have Xerox copies of people; you can't have clones of people that will be the same. "
One area where the study of genes is expected to have an impact is in identifying mental disorders with genetic roots, perhaps reducing the stigma of conditions such as depression or schizophrenia. Researchers are also closing in on stretches of genetic code that may make an individual more vulnerable to developing drug or alcohol addiction.
Following the finding that we have fewer genes, further research may be conducted into

A. how the genetic sequence influences the relationship between genes and behavior.
B. why environmental influences play a greater role in our growth.
C. why inheritance plays a less role in shaping our destiny.
D. how the genes are combined to create the incredible complexity of man.