By Helen Briggs

Five genetic clues to why some women have a family history of breast cancer have been identified by UK researchers.

It brings to 18 the number of common genetic variations linked to a small increased risk of breast cancer.

The Cambridge University-led research, published in Nature Genetics, could see targeted screening and treatment of women more likely to get breast cancer.

It is thought about one in 20 of all breast cancers are down to inherited faults in known genes.

Breast cancer is the most common cancer in the UK with more than 45,500 new cases diagnosed each year.

The precise reasons why a woman develops the disease are still unknown.

However, inherited, environmental and lifestyle factors are all thought to play a role.

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