Smoking linked with increased risk of most common breast cancer
Young women who have smoked a pack of cigarettes per day for a decade or more are 60 per cent more likely to develop oestrogen receptor positive breast cancer, the most common type of breast cancer, a study in the journal Cancer has found. In contrast, no link was found between smoking and triple-negative breast cancer, which is less common but more aggressive. The study analysed nearly 1,900 women aged between 20 and 44 years old. They found 778 patients with oestrogen receptor positive breast cancer and 182 patients with triple-negative breast cancer. The control group was made up of 938 cancer-free women.
Seven new genetic regions linked to type-2 diabetes
An international consortium of researchers, co-led by investigators from Oxford University, have identified seven new genetic regions associated with type-2 diabetes in the largest study yet on the genetic basis of the disease. DNA data was gathered from more than 50 studies worldwide - a total of more than 48,000 patients and 139,000 healthy controls of European, Asian and Hispanic backgrounds. Among the regions identified are two that also show strong links to elevated levels of insulin and glucose in the body - two key characteristics of the disease. "These findings may lead us to new ways of thinking about the disease, with the aim ultimately of developing novel therapies to treat and prevent diabetes," says first author Dr Anubha Mahajan of Oxford. The study appears in Nature Genetics.
Why women and men differ in height
University of Helsinki scientists have identified a genetic variant that could explain why women tend to be shorter than men. The study, published in PLOS Genetics, analysed chromosome X, one of the two sex-determining chromosomes, in almost 25,000 northern European people. The identified variant was frequent among shorter people and present in more than a third of Europeans. It was also found to increase the expression of ITM2A, a gene that has a role in cartilage development, suggesting that the more the gene is expressed, the shorter the person will be. The effect of this variant on height was shown to be much stronger in women.