SAN FRANCISCO _ In 5 to 10 years, gene discoveries will be sonumerous tests will be available for predisposition to a lengthy list ofdiseases, but a consensus of public, government and businessinterests on how to use that information does not exist.
An immediate problem, said Francis Collins, head of the NationalCenter for Human Genome Research (NCHGR), is the potential forgenetic discrimination by insurance companies.
No federal protection, for example, exists to stop insurance carriersfrom dropping coverage on women who test positive forsusceptibility to breast cancer, a genetic test already available.
Collins said six bills in Congress address the issue. A proposal bySen. Nancy Kassebaum (R-Kan.) includes a provision preventinghealth insurers from denying coverage for pre-exsisting conditions.Another issue, Collins said, is what to do with information about agenetic mutation that heralds a disturbing future when no treatment orcure exists to correct it.
Collins again used the example of breast cancer, whose underlyingcause was pinpointed last year with the much-publicizedidentification of the BRCA1 gene, which was linked to familial andsporadic cancers. (See a related story on p. 1 of this issue.)
Discovering a predisposition to the disease could result in earlydetection at onset, but no effective treatment has been found. Evenwomen who have prophylactic surgery to remove breasts once theydiscover their susceptibility are not guaranteed they won't developthe cancer.
Questions about whether genetic tests should be made availablewithout regulations for their use and without warnings to consumersabout consequences have not been answered, Collins observed.
Eventually preventive treatments may be available, but technologyfor testing is here now. Collins said ethical, social and legalconsiderations on how to handle such life-altering diagnoses have tokeep better pace with the science.
The federal Equal Employment Opportunity Commission took a firststep last year, ruling employers cannot discriminate on the basis of aperson's genetic profile.
Collins raised the public policy issues in the context of discussingprogress of the U.S. Human Genome Project at a conference here oncommercial implications of the worldwide effort to sequence theentire human genome. As head of the NCHGR, which is funded byboth the National Institutes of Health and the Department of Energy,Collins directs the U.S. part of the global effort to sequence the entirehuman genome.
The project, begun in 1985, reached a major milestone late last yearwhen a physical map of all 23 pairs of chromosomes was completed.The map contains more than 15,000 DNA markers spread every 199kilobase pairs. By the end of this year those markers will double toevery 100 kilobase pairs.
The physical map, Collins said, sets the stage for reaching the goal ofdecoding all 3 billion base pairs of DNA that form the fundamentalcomposition of human beings.
To date, he noted, a tiny fraction of the genome has been sequenced.
Collins said the large-scale sequencing effort could be finished by2003, two years ahead of schedule. The project is an internationaleffort and Collins estimated the U.S. will provide about half the datato the finished DNA sequence map.
Final decisions have yet to be made on institutes and researchorganizations that will receive grants to conduct the work. A $15million pilot project will be launched soon.
The complete DNA sequence of the human genome will provideresearchers a better tool for locating disease genes and pinpointingtheir functions.
What Happens When The Map Is Complete?
As for what happens to the U.S. Human Genome Project after theDNA sequence map is complete, Collins had some ideas for keepingthe program alive.
The project, he said, could support continued development of fastersequencing technology making it possible eventually to sequencenumerous human genomes.
"After we sequence one genome, people will want to do more," hesaid.
Then there's support for determining how genes interrelate throughlarge-scale expression of multiple genes, which would help analyzepathways that trigger certain biological responses, such as an immunesystem attack on invading pathogens.
"Most identification of pathways today is incredibly simplified,"Collins said.
Learning more about evolutionary biology is another area the HumanGenome Project could support, he added, along with assisting inanalysis of population biology; that is, identifying diseases peculiar toracial and ethnic groups.
Finally, Collins said, the Human Genome Project could continuefunding efforts to understand the sweeping ramifications of reducinglife to its genetic realities.
The NCHGR currently funds an effort to devise public policyrecommendations for some of those ethical, legal and socialimplications, particularly with respect to genetic testing. n
-- Charles Craig
(c) 1997 American Health Consultants. All rights reserved.