Pharmaceuticals giant GlaxoSmithKline (GSK) has acquired five million newly-issued shares in Response Genetics, taking its stake in the company to around 15.2 per cent. GSK purchased the shares at 110 cents each in cash. "This transaction builds on the relationship GSK and Response Genetics have been building over the years in the diagnostics field of oncology and vaccines," the firm said in a statement. Response Genetics performs companion diagnostic tests and other related activities for GSK's immunotherapies and oncology pipeline candidates.GSK's share price rose 0.91% to 1,434.50p by 14:52.NR