Roche makes $5.7bn bid for Illumina A year earlier, Roche snapped up diagnostics company Ventana Medical Systems for $3.4bn, having increased its original offer by 19pc. Roche said that it had tried to negotiate a deal with Illumina, but had decided to make an offer after being unable to participate in "substantive discussions" with the company. Illumina said it would "thoroughly review" Roche's proposal and make a recommendation to stockholders in due course that it believes is in the best interests of investors. The US company's systems analyse an individual's DNA and gene sequencing is seen as central to personalised medicine, which allows scientists to predict a patient's response to a particular drug and target medicines at those who could benefit the most. Daniel O'Day, Roche's head of diagnostics, said that together, Roche and Illumina would be able to acclerate the transition of sequencing into routine diagnostics, potentially developing companion diagnostics that could then be paired with specific treatments. Analysts raised the prospect of similar deals within the diagnostics market. Navid Malik, a pharmaceuticals analyst at Cenkos, said: "This hostile deal demonstrates the urgency with which a number of blue chip pharma and diagnostics companies are seeking to bolster their market share."