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From New Scientist magazine, 11 March 2000.

                          Nowhere to hide

                          A gene profiling system threatens to reveal
                          your innermost secrets

                          WILL "DNA chips" that reveal your genetic makeup within
                          minutes prove to be awesome medical tools or the means of
                          genetic discrimination? We could find out sooner than
                          anyone expected. A British biotech start-up has filed for a
                          patent on a device that can detect variants of over 2500
                          genes--including genes that affect behaviour and intelligence.

                          Researchers with the company Genostic Pharma of
                          Cambridge have worked out the blueprint for a system which,
                          they believe, can provide a "core" genetic profile of any
                          individual. The automated device uses DNA
                          chips--essentially sensors that can detect many thousands of
                          gene fragments at once. The company expects to start
                          making prototype chips within months.

                          It says that the device will help doctors to find out if people
                          are predisposed to particular diseases and tailoring
                          treatments to individuals. But such devices could also be
                          used by unscrupulous employers or insurance companies to
                          reject applicants with "the wrong genes".

                          Rival DNA chip systems tend to focus on gene variations
                          relevant to just one disease, such as breast cancer, or to a
                          potential adverse drug reaction. But Genostic Pharma's chip
                          gives medically relevant genetic information about 16
                          different types of disease (see Figure), says the company's
                          founder Gareth Roberts.

[log in to unmask]" ALT="Chart: Your health on a chip - medical area vs. number of genes and variants" BORDER=0 height=364 width=302>
 

                          Roberts and his colleagues at Genostic Pharma combed the
                          scientific literature for common gene mutations called
                          single-nucleotide polymorphisms, or SNPs, which can alter
                          people's predisposition to disease or their reaction to drugs
                          (New Scientist, 14 November 1998, p 32). They then plucked
                          the entire sequences for these genes out of publicly available
                          sequence databases. In a 700-page patent application,
                          Roberts lists all the chosen genes plus known variants.

                          To create its genetic profiling system, Genostic Pharma must
                          take short stretches of DNA from each variant of each gene
                          and fix them to a specific spot on the surface of the DNA
                          chip. To test a blood or saliva sample, researchers will break
                          down its DNA into fragments, attach fluorescent markers and
                          wash them over the chip. The fixed DNA strands will grab any
                          matching gene fragments that pass by. The fluorescent tags
                          will then reveal by their position the identity of each gene
                          captured from the sample (New Scientist, 14 November
                          1998, p 46).

                          The genes Roberts has chosen to include on the profiling
                          chip are the ones he thinks are relevant to a range of
                          conditions, from cancer and heart disease to headaches and
                          impotence. But others doubt enough is yet known about the
                          human genome for Roberts to make these choices.

                          "Where Genostic comes up with thousands of gene variants
                          to put on their chip is a mystery to me," says Francis Collins,
                          director of the US National Human Genome Research
                          Institute near Washington DC. Daniel Cohen, chief genomics
                          officer at Genset of Paris, agrees. "There haven't been
                          enough population studies, as far as I know, to assess with
                          enough precision the risk or predisposition for any of the
                          diseases mentioned in the patent," he says.

                          Others are not convinced that the chip is intended for entirely
                          therapeutic purposes. The patent lists 500 variants of genes
                          related to psychoses and personality, for example, as well as
                          250 linked to behaviour. "It creates a set of issues way
                          beyond medical applications," says Onora O'Neill, former
                          chair of Britain's Human Genetics Advisory Commission.

                          More at: www.derwent.com/resource/interest.html
                          www.newscientistjobs.com/real/frame_real_lives.html

                          Andy Coghlan
http://www.newscientist.com/news/news.jsp?id=ns222927
--
Ivan Handler
Networking for Democracy
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