UPDATE 1-U.S. court denies Sequenom's motion against Ariosa

July 6 (Reuters) - A U.S. district court rejected Sequenom Inc's request for a preliminary injunction against privately held Ariosa Diagnostics from selling prenatal tests for detecting abnormalities in chromosomes.

The genetic analysis products maker filed a motion in February alleging that Ariosa infringed its patent on a test for detecting a genetic chromosomal anomaly known as Trisomy 21.

Sequenom makes and sells MaterniT21 - a test to detect certain chromosomal abnormalities, including Down Syndrome. Down Syndrome is a chromosomal disorder that affects infants, resulting in impaired cognitive ability and abnormal facial features.

Shares of the company were trading down 3 percent at $3.96 on Friday on the Nasdaq.