There are few products that could not only take a huge market share, but also grow the market at the same time -- Apple's (NASDAQ:AAPL) iPod or Intuitive Surgical's (NASDAQ:ISRG) da Vinci Surgical Systems are some examples. Early data from Sequenom (NASDAQ:SQNM) suggest that it might be the next big thing -- albeit in a less sexy market.

On Wednesday, Sequenom announced that its prenatal Down syndrome test was able to use maternal blood to correctly identify the 10 Down syndrome samples from the 201 tested samples without any false positives (that is, saying there is one when there isn't). Current tests available can only identify 70% to 90% of samples with a false positive rate of up to 5%.

In addition, Sequenom's test is non-invasive, using a sample of the mother's blood only. This avoids the risk of miscarriage, among other risks, in  amniocentesis, where some of the amniotic fluid in the womb is withdrawn for testing.

Obviously, the next step is to examine a larger sample population. If the test continues to perform with this high rate of detection and no, or very few, false positives, Sequenom could grab much of the estimated $1 billion Down syndrome testing market. And, because the test appears to have a much lower risk to the patient, we could see it being used on patients who wouldn't be given any test with what's currently available. Guess what? That increases the testing market.

Believe me, those two possibilities have not been lost on investors, either. The company's stock jumped nearly 22% Wednesday and is up a further 21% so far today.

Like other diagnostic test developers, Sequenom has its roots in developing research tools for scientists, and only recently moved into diagnostic testing. But unlike the other research-supply turned-diagnostic-testers, like Affymetrix (NASDAQ:AFFX) or Illumina (NASDAQ:ILMN), Sequenom isn't profitable ... yet. That makes any investment a bit more risky, but the rewards are also potentially greater.

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