Roche Holding AG Chairman Franz Humer may have put a lid for now on a year’s worth of speculation by telling a Swiss newspaper that a Roche deal to buy U.S. genetics company Illumina Inc. is off the table. Illumina shares fell in trading before U.S. exchanges opened.

The interview “discounts Roche’s intent to purchase Illumina medium-term,” Ross Muken, a New York-based analyst for ISI Group LLC, wrote in a note to investors late yesterday. “We do not believe this precludes Roche from returning to Illumina as a targeted asset in the future and does not diminish its attractiveness as a potential M&A target.”

The two companies’ names have been linked since speculation about a deal first surfaced in December 2011. Illumina spurned Roche’s hostile bid in January 2012 of $44.50 a share and a sweetened, $51-a-share proposal, and the Swiss company walked away after investors held out for an even higher offer. A Swiss newspaper, L’Agefi, reported last month that the companies had agreed to a $66-a-share deal.

While Roche was aware that Illumina was sending conciliatory signals, no deal resulted, Humer said, according to an interview published yesterday in Switzerland’s SonntagsZeitung.

“Illumina is definitively off the table,” Humer said. “The other side wasn’t ready to retreat from their totally excessive price demands. Roche doesn’t do acquisitions that don’t create added value. We have self-discipline.”

Stock Drops

Illumina fell 12 percent to $48 at 7:05 a.m. New York time in trading before U.S. exchanges opened. The stock had gained 93 percent in the past year.

Illumina would have been a “nice-to-have” deal, not a “must-have” asset, SonntagsZeitung quoted Humer as saying. Alexander Klauser, a spokesman for Roche, confirmed Humer’s comments.

History shows a pattern of Roche acquiring “emerging or nascent” gene-sequencing assets, such as NimbleGen Systems Inc. and 454 Life Sciences, Muken wrote, while the only time it bought a market leader close to Illumina’s stature was in its 2008 purchase of Ventana Medical Systems Inc. The ISI analyst has a “market weight” rating on Illumina’s shares.

Roche sees other alternatives for adding gene-sequencing technology, SonntagsZeitung cited Humer as saying.

Illumina asked for $68 a share on Dec. 28 and $75 a share on Jan. 3, L’Agefi reported today on its Twitter feed, without saying where it got the information.