Human Genetics and the Fight Against Cancer

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Gene Sequencing

When the first draft of the human genome was published in 2000, the then US president Bill Clinton said, “We are beginning to learn the language that God created life.” It was a landmark moment in the history of genetics to equal that of Crick and Watson’s discovery of the structure of DNA.

Knowledge of how our genes are put together offers us some of the best hope that diseases such as lung cancer, bone cancer, and prostate cancer will be defeated. The confidence is based on developments in genetic sequencing technology and the power that will soon be available to rapidly sequence genes and compare individual genomes. This will make it much easier to look for patterns that make some people more susceptible to cancer than others. At its most fundamental level cancer is caused by bad genes, mutations that cause a cell to go haywire and grow out of control. The more we know about the molecular basis of what goes wrong, the better our chances of success. There are now several companies developing technologies to be able to rapidly sequence genomes. Some are involved in the race to be the first company to sequence an entire human genome in under a day for $1000.

Comparing Genomes

DNA is the blueprint of life, the biological plan to make you and me. It’s written in an alphabet of four chemical letters - the bases A, T, G, and C. Variations of these letters make genes which code for all the different proteins that our bodies need to function. And there are millions of tiny variations between our genomes. These are called SNPs (single nucleotide polymorphisms) and many are harmless, whilst others can make us more or less susceptible to disease.

Research into the genetic basis of diseases such as cancer is based on limited information from relatively small sections of DNA. But if scientists were able to compare thousands of whole genomes they might be able to see patterns emerging. The benefits would be; improved diagnostics and therapeutics, personalised medicines and increased understanding of the complex interplay between genes and environment in the onset and development of many cancers. Making all this possible are advances in biotechnology, nanotechnology, and increased computer power.

For some scientists the long-term goal is a world where a child has its genome sequenced at birth or shortly thereafter, and that this information is constantly referred to during an individual’s life to spot early warning signs and maintain optimum health.

Beware of False Hope

Of course we must be patient, scientific progress is slow and methodical. Even when a scientist shouts out ‘Eureka’ it could be many more years, generations even before a meaningful application is available. Just look at gene therapy; not yet a common procedure despite years of intense research and many clinical trials. But is the idea that cancer could be beaten really that far fetched? The odds may appear to be stacked against us, but then again flying to the moon, international flights, and television were all once ‘impossible’ ideas.