Swiss drugmaker Roche would still consider buying a gene-sequencing company to fit its strategy of tailoring treatments to specific patients, after dropping a $6.8 billion bid for one earlier this year.

Roche has forged ahead with personalized therapies and is investing in the fast-growing field of gene-sequencing which will help to better predict which patients are likely to respond to a particular drug.

In April, however, it walked away from a $6.8 billion bid to buy gene-sequencing market leader Illumina - which makes machines that decode a person's genome, or genetic code - after shareholders blocked its move to gain seats on the U.S. firm's board.

Roland Diggelmann, chief operating officer of Roche Diagnostics, said the company was investing in its existing activities, including automation and sequence capture, but would still consider an acquisition.

"We continue to be open to external opportunities and technologies," Diggelmann, who became COO in September, told Reuters in an interview on Tuesday.

"It would probably be medium-sized, which would really be bolt-on technologies."

Roche is the world's largest maker of cancer drugs as well as a market leader in diagnostic tests.

While it is still unclear how gene-sequencing will be used routinely in a clinical setting or exactly how it will be regulated, firms like Roche hope the technology will expand as drugmakers adopt more medicines that target specific genes.

Diggelmann said the company was well-positioned in long DNA sequences, known as "long reads", but had a less-favourable position in short sequences.

He said Roche currently lagged Illumina and Life Technologies in the gene-sequencing field.

"I would say we come number three. There are certainly very many small start-up companies, companies that develop new approaches to sequencing. But in terms of those that have a commercial presence I would say it is probably the three of us," he said.

Diabetes in the doldrums

One problem for Diggelmann to tackle is Roche's Diabetes Care business, one of five units in the diagnostics business, where sales fell 5% in local currencies in the first nine months of 2012 to 1.84 billion Swiss francs ($2 billion).

Makers of blood glucose monitoring and insulin delivery systems such as Roche have faced stiff competition from low-cost manufacturers which has pressured sales. But Diggelmann said the long-term growth potential remained compelling.

"It is a business that continues to see growth in patient population and that is probably why you see so many players in this segment," he said.

"The pressure in the market is there and I do not think the pressure will ease. For us it is important that we adjust our organisation to the current business environment," he said, adding that Roche was addressing costs and looking at how to differentiate its products.

About 347 million people have diabetes worldwide, according to estimates from the World Health Organisation, and that figure is rising due to growing rates of obesity.

Diggelmann said Roche - which bought Elron Electronics' Medingo unit to broaden its range of insulin delivery systems in 2010 - was always looking at technologies in the area.

Although rival Bayer pulled the plug on a sale of its blood glucose meter business due to a lack of sufficient interest in buyers, Diggelmann still expects some consolidation in the field.

"Certainly there will be some consolidation. But who and when - that is really hard to predict"