Genetic Code Cracked for Two Cancers

[Angel]

Scientists at Johns Hopkins Kimmel Cancer Center in Baltimore say they have identified 200 mutated genes linked to breast and colon cancer. Most of the genes were not previously associated with tumor initiation, growth, spread or control.

Efforts to map cancer genes are happening in many labs across the country. Scientists hope it will lead to more successful detection and treatment strategies. The work is painstakingly slow and tedious.

The researchers at Johns Hopkins in Baltimore began with 11 samples each from breast and colon cancer patients. Within each tumor cell are billions of individual chemicals called nucleotides that pair together to make the genetic structure. Changes in these nucleotides can cause a normal cell to become a cancerous cell.

Researchers examined the DNA code of 13,000 genes by dividing them into overlapping sections. They fed the sequences through computer software that matches up normal sequences with those from tumor samples. In the end, the team of scientists combed through 465 million nucleotides to find 1,500 that differed from the normal code. Through further examination, they found the 200 genes that were significantly changed or mutated.

The authors report the mutated genes in breast and colon cancer were almost completely distinct, explaining why each type of cancer is a very different disease.

The goal is to use these findings to help create new cancer drugs, report the authors.