Gene linked to breast cancer survival

Genetics is a funny business. While the promise of personalised medicine is enticing, it's not always as simple as targeting one gene and linking it one-for-one with a disease.

Sometimes the gene that influences the outcome of some disease is also linked to many other aspects of our biology and health.

A new discovery by researchers at the Queensland Institute of Medical Research has found that a gene commonly associated with skin pigmentation, hair and eye colour plays some role in influencing survival rates in breast cancer patients.

This gene, OCA2, could represent a new target for breast cancer treatments, but it's complicated - like many other genetic treatments - by the fact the gene is responsible for other things as well.

The researchers found that a rare variant in the OCA2 gene increased the survival rate of patients with oestrogen receptor negative breast cancer.

“Among these patients, those with the rare variation had a predicted survival rate of 83 per cent at 10 years, compared to the common variant, which we found had a predicted 60 per cent survival after 10 years,” said Professor Georgia Chenevix-Trench, of the QIMR.

The study included 3,700 breast cancer patients, which makes the difference in survival rates highly significant.

The researchers also hasten to add that there is no link between specific eye colours and cancer survival, even though the OCA2 gene influences eye colour.

The research was led by Dr Paul Pharoah from the University of Cambridge and completed in collaboration with Breast Cancer Association Consortium researchers from Europe and the USA.

The findings have been published in the Journal of the National Cancer Institute and the paper is currently available online.