Cancer breakthrough as scientists find a ‘treasure trove’ of genetic clues

Analysis of thousands of tumours from NHS patients has identified a ‘treasure trove’ of new clues about the causes of cancer.

In the biggest study of its kind, researchers at Cambridge University Hospitals looked at the genomes of more than 12,000 people with cancer in England.

They spotted 58 new patterns in their DNA, called mutational signatures, suggesting there are causes that scientists are not yet aware of.

The researchers hope the discovery will allow future studies to work out the root of these cancer-causing mutations.

Scientists were aware of just 51 mutational signatures before the new find, including changes caused by smoking or UV light.

Identifying these signatures also allow doctors to look at each patient’s tumour and match it to specific treatments and medications.

However, the patterns can only be detected in cancer patients who have had their whole genome sequenced by scientists — which isn’t routinely done.

Professor Serena Nik-Zainal, a genomic expert who led the study, said these patterns are like ‘fingerprints at a crime scene’.

She said the findings could indicate an ‘Achilles heel’ in individual cancers that could be targeted with treatment.

Cambridge University researchers studied the genetic make-up of more than 12,000 people with cancer in England, which allows them to see the origins of the tumour. They spotted 58 new patterns in the DNA of cancer, suggesting there are causes that scientists are not yet aware of

HOW DOES CANCER DEVELOP?

Cancer starts in the cells.

Inside almost every cell in the body is a copy of your genome, made of DNA.

The genome can be thought of as the instructions for running a cell. It tells the cell what kind of cell to be — such as a skin cell or a liver cell — and has instructions that tell the cell when to grow, divide and die.

When a cell divides to become two cells, the genome is copied. Usually this happens in a controlled way and is how bodies grow and repair.

But sometimes mistakes happen when copying the genome. These are called mutations.

The mistakes can be caused by natural processes in the cells, by chance, or by external factors, such as UV light or smoking.

Most damage is repaired immediately with no negative effects.

But sometimes the mutations in critical genes means it no longer understands its instructions and multiplies out of control.

The abnormal cell keeps dividing and making more and more abnormal cells. These cells form a lump, which is called a tumour.

Source: Genomics England

Around 375,000 new cancer cases are diagnosed in the UK every year, while 1.7million are confirmed in the US.

Cancer is caused by mutations in the genome of cells, which causes cells to multiply out of control until they form a tumour.

The latest study, published in the journal Science, analysed the whole genome of 12,222 NHS cancer patients as part of the 100,000 Genomes Project in England.

Genome sequencing looks at all of the thousands of DNA building blocks within each tumour, showing the mutations that contribute to each person’s cancer.

Some of the new mutational patterns observed were present across many different cancer patients, while some were more rare.

Cancers are…