ZURICH (Reuters) - Roche has no plans to warm up its play for Illumina after its takeover bid for the U.S. gene sequencing firm failed, and will pursue smaller takeovers instead, Chief Executive Severin Schwan says in an interview on Sunday.

"We are constantly looking at the market, and will concentrate on smaller and mid-sized acquisitions," Schwan was quoted as saying in Swiss weekly Sonntag.

Roche effectively walked away from a $6.8 billion hostile offer for genetic specialist Illumina in April, saying a higher offer would not be in the interests of its own shareholders.

Roche will also invest an undisclosed sum in its own gene sequencing research, which is technology Illumina has that would have helped Roche in its bid to develop targeted patient therapies.

(Reporting By Katharina Bart; Editing by Jon Loades-Carter)