GERMANTOWN -- The deliveries that arrive at this quiet, nondescript suite, tucked away in a shoe box of an office building just off Interstate 270, are anything but nondescript: A hair. A bloodstained swatch of fabric. A lipstick-smudged cigarette butt. A torn fingernail. An ax.
They are all remnants of sordid episodes of murder, rape, acts of betrayal.
Each item will be combed for a trace of human life, a genetic calling card that can be used to help answer such questions as: "Who killed JonBenet Ramsey?"
Cellmark Diagnostics is the nation's largest private forensic laboratory for testing of DNA (deoxyribonucleic acid), the material that contains an organism's genetic code and transmits the hereditary pattern.
The lab first achieved international celebrity when it performed tests on blood samples for the O. J. Simpson murder trial and its lab director testified in court.
The company's fortunes have soared in the past couple of years, with its workload growing 20 percent each year, its staff expanding, plans in the works for a move to grander digs this year -- and more sensational, high-profile murder cases landing at its heavily secured front door in this Montgomery County suburb.
Most recently, the Maryland lab, which specializes in criminal investigations but also performs DNA testing to determine paternity, has been examining evidence connected to the slaying of JonBenet Ramsey, the 6-year-old pageant winner in Boulder, Colo.
Its work is expected to be finished possibly as soon as this week.
In the past decade, the field of DNA testing has exploded, with Cellmark -- which opened in 1987 with a sister operation in England -- among a field of 130 public and a dozen private crime labs in the country doing such analysis.
Considered the blue-chip private lab for DNA "fingerprinting" by those in the forensics industry, Cellmark tests samples of body fluids and other biological evidence for 500 to 600 cases a year, most of them murders or sexual assaults, from all over the Western Hemisphere.
"What we are doing is to establish identity beyond a reasonable doubt in the mind of a juror," says Cellmark's director of operations, Mark D. Stolorow.
"By examining four or five or six points on a person's DNA, we can reach a level of individuality which can answer the questions in the courtroom for whose blood matches the evidence at the crime scene and whose blood does not."
At this modest suite of laboratories, there is little to suggest the intrigue, the violence, the life-or-death dramas that often hinge on the white, gelatinous blobs -- DNA -- that float in tiny test tubes.
The main lab is bright, quiet, still -- and dotted with signs that caution "Radioactive Materials" or "Biological Hazard, Wear Your Goggles."
Behind an unmarked, locked door is the evidence vault lined with refrigerators and freezers that contain the samples of blood and other biological materials that have been either hand-delivered or shipped to the lab.
Another room holds the larger pieces of evidence -- a sofa, a headboard, a car door, a piece of pavement -- that occasionally arrive, often with invisible stains of body fluids that scientists can detect with a laser.
Cellmark's scientists -- the company employs 15 molecular biologists among its staff of 35 -- have testified in about 400 trials (for a fee of $1,200 a day plus expenses), 90 percent of the time for the prosecution.
Role in conviction, appeal
Such testimony, for instance, played a key role in the 1995 murder conviction of Scotland E. Williams, who was sentenced to death in the slayings of two lawyers near Annapolis.
In an extraordinary combination of detective work and science, DNA was extracted from mouth cells lifted from a drinking glass left at the crime scene. It matched Williams' DNA, a Cellmark scientist told the court.
But that DNA testimony also led in part to the Maryland Court of Appeals' decision to grant Williams a new trial.
The state's highest court ruled in July that Williams' lawyers, who claimed such DNA testing techniques were susceptible to contamination, were not allowed sufficient opportunity to cross-examine the Cellmark scientists about the frequency of contamination at its lab.
A new trial is scheduled to begin Nov. 3.
Another high-profile case was a 1988 murder in which no body was found. Gregory Tu, a Potomac restaurateur, was convicted of first-degree murder in the disappearance of his common-law wife, Lisa Tu, after bloodstains on the basement floor yielded DNA determined to be hers.
The lab took blood samples from Lisa Tu's first husband, who was living in Hong Kong, and their teen-age son.
From their DNA patterns, scientists could determine what hers must look like. A Cellmark scientist testified in court that it was "extremely unlikely" that the blood in the basement came from anyone other than Lisa Tu.
Proof of innocence