Genetics smartcard

KeywordsAutomation, Cybernetics, Research, Technological developments

Abstract Gives reports and surveys of selected current research and development in systems and cybernetics. They include: Human cells may process information, Artificial brain, Genetics smartcard, Robotic revolution, Application of AI, New devices in medicine, Innovations in cybernetics and systems.

Genetics smartcard

DNA microarray

Yet another device has been produced that is no bigger than a credit card but can carry a great deal of data. The device, we are told, is likely to revolutionise biology and indeed all fields that use related information. This particular device will carry 10,000 fragments of information of DNA and is a microarray that will have importance in diagnosing disease; assessing an individual's risk of cancer or heart disease;or monitor the progress of a drug treatment. Any information that is required to be stored conveniently and made readily available can be entered and then used.

A particularly important use of the smartcard's microarray is in genetics and an example of its use was given in Nature Genetics and republished in many other widely circulated reports in December 1998.

It was reported that the research team of the Medical Research Council's Clinical Sciences Centre at the Hammersmith Hospital, London, UK, had used the microarray to identify a gene in rats that causes a condition akin to insulin resistance syndrome in human beings. One of the reports says that:

It is important not only because the syndrome is an early pointer to obesity, diabetes, high blood pressure and heart disease, but also because it illustrates the power of the microarrays to penetrate the genetic jungle and pinpoint a single tree.

The microarray consists of a solid surface of glass or silica, with single-stranded fragments of DNA arranged in columns and rows across its surface. It is made in a similar way to that of building a silicon circuit. The final product is a flat surface with a huge number of short lengths of DNA floating from it, like tendrils of seaweed rising from the ocean floor, we are told.

Using the genetic chip

The genetic chip is used by first taking a sample from a patient, purifying it and splitting it into single strands. These are then cut into short pieces with each piece tagged with a fluorescent molecule. The chip is then washed over. Where DNA strands in the mixture hit a complementary sequence on the chip, they bind. The better the match, we are informed, the stronger the bond. The chip is then washed over with a chemical which will break all but the strongest bonds. It is then, finally,that a computer is used, first to read the position of the fluorescent tags that are still attached to the surface, and then to match them to the original length of DNA attached to that site.

What is happening is that the microarray is being used to interrogate a DNA sample and to identify the DNA sequences within it.

A spokesman for Affymetrix,California, USA, a company which has pioneered the technology says that:

In a single afternoon,people have confirmed work that took several years using conventional gene sequencing processes.

Apart from the reports quoted here Nature Genetics has issued a special supplement on this technology,called the "Chipping Forecast" it is available on the internet site at: http://genetics.nature.com

This is one of the many devices which will contribute to the diagnosis of disease. It is predicted that in the future perhaps the entire human genome will be held on one or more smartcards of this type. The possibilities, then, are just enormous.