Genetikken kommer med overraskelser. Ikke bare fungerer medisiner ulikt på forskjellige etniske grupper. De gir også forskjellige utslag på enkeltindivider, og det er genetisk betinget.
Det er fantomet Craig Venter som går ut med dette. Han mener som kjent at forebyggende medisin blir den viktigste arena for helsearbeid i fremtiden, med genetiske kart over hver enkelt som standard.
Venter and three scientists from the Craig Venter Institute in Rockville, Maryland vigorously defend the focus on minorities in drug studies, but argue that race-based medicine should be seen only as an imperfect stop-gap measure.
«Practitioners can now go beyond therapy on the basis of ethnicity into the precisely targeted arena of personal genomics,» they write.
The high degree of genetic diversity within single ethnic groups, they point out, shows that assumptions about shared traits are deeply flawed.
To underscore the point, the scientists compared the genetic makeup of two Caucasian men whose entire genomes have been sequenced — American biologist James Watson, who won the Nobel Prize in medicine for co-discovering the structure of DNA, and Venter himself.
In 2000, a team led by Venter and a publicly-funded rival effort simultaneously unveiled the world’s first two completely sequenced human genomes.
Writing in the journal Clinical Pharmacology and Therapeutics, Venter and his colleagues looked at six genes known to play key roles in metabolising medicine.
Three of the genes were identical, but the other three showed variations that could result in sharply different reactions between the two men to several common drugs.
Venter, for example, had a variant of the CYP2D6 gene that helps metabolise certain medications prescribed for depression, psychosis and arrhythmia, an irregular beating of the heart.
In Watson, however, the same gene was different enough such that none of these drugs would be likely to function as intended.