Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of biotech Sequenom (Nasdaq: SQNM) surged more than 11% in intraday trading after reporting strong first-quarter results and the successful completion of a clinical study of its diagnostic Down syndrome test.

So what: The company's Trisomy 21 (T21) test promises a non-invasive means to test for Down syndrome in unborn children. According to the earnings release, results for the latest round of T21 results won't be published until later this year.

Now what: In the meantime, Sequenom's first quarter ended with a $0.13-per-share loss on $13.5 million in revenue. Analysts had been expecting a $0.19-per-share loss on $12.7 million in revenue. Traders and investors alike cheered. But for Fools, this three-star stock remains a speculative bet. Tread carefully.

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Fool contributor Tim Beyers is a member of the Motley Fool Rule Breakers stock-picking team. You can try any of our Foolish newsletter services free for 30 days.

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