DNA cold case: las Vegas authorities announced July 21, 2021, the a Texas forensics lab had taken a small amount of hereditary material — the tantamount of fewer than 15 human being cells — and also identified the alleged killer the Stephanie Isaacson, 14, that was slain June 1, 1989, top top her means to school. Darren Marchand, pictured in a 1986 booking photo, eliminated himself in 1995. (Las vegas Metro Police Department)

July 28, 2021 in ~ 4:12 afternoon PDTBy crystal Bonvillian, Cox Media team National contents Desk

LAS las vegas — when 14-year-old Stephanie Isaacson was uncovered bludgeoned, raped and strangled in an empty las Vegas sandlot in 1989, police had small to go on other than a small amount of DNA on her shirt.

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The instance went cold and also stayed that means for 32 years.

Authorities announced July 21 the a Texas forensics lab had taken the tiny quantity of genetic material — the indistinguishable of fewer 보다 15 human cells — and identified the teen’s alleged killer. The minuscule DNA sample is the the smallest amount ever before used to settle a case, las Vegas city police public official said.


The material, merged with genetic genealogy research, has connected Darren Roy Marchand come Stephanie’s murder. Marchand, that was accused the a similar murder 3 years prior to Stephanie’s death, committed suicide in 1995 at the period of 29.

“I’m glad they discovered who murdered mine daughter,” Stephanie’s mother, whose name was not released, stated in a statement read by police. “I never thought the instance would be solved.”

Stephanie vanished the morning that June 1, 1989, together she walked she usual path to Eldorado High School, cutting with a sandlot top top the way. Follow to authorities, she father acquired worried as soon as she no return house that afternoon and called the school.

He learned from the former office the his daughter had actually never do it come class.

“At that point, she father contacted every one of her friends, and also none that them had actually seen her at school that day,” claimed homicide Lt. Beam Spencer.

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DNA cold case: Lt. Ray Spencer speak July 21, 2021, as ras Vegas police officials announce exactly how a minuscule amount of DNA evidence helped deal with the 1989 rape and also murder of 14-year-old Stephanie Isaacson. (Las vegas Metro Police Department)

Stephanie’s panicked father referred to as the police.

“At that time, metro police began an exhaustive air and also ground search attempting to find Stephanie,” Spencer said.

Around 8:40 p.m. The evening, several of the teen’s textbooks and also other belongings were spotted strewn close to the intersection the Nellis Boulevard and also Stewart Avenue, which in 1989 to be still a “desert area,” police said.

Search parties trying to find the lacking girl uncovered her body around 25 yards turn off the trail she take it to and also from college each day.

Stephanie’s autopsy verified that she’d endured “significant blunt pressure trauma injuries and also that she had been sexually assaulted,” Spencer said. Her reason of death was strangulation.

Las las vegas detectives began a decades-long examination to identify who had actually killed the teen. Many potential suspects to be identified and eliminated, and investigators traveled throughout the nation following increase on leads.


Truly honored to have the ability to assist the ras Vegas metropolitan Police room in identify the doubt to the sexual assault and murder of Stephanie Isaacson. This ID to be made with 120pg DNA, a record-low quantity: https://t.co/u1DqDVdX13

— Othram Inc. (

Kim Murga, head of the department’s forensics lab, said the DNA evidence had to be tested multiple times over the years as an innovation improved. It was not until 2007, however, the the stain top top Stephanie’s shirt provided a DNA profile of her killer.

Over the following 13 years, the lab compared the unknown male DNA file to much more than 30 samples built up in the case. No one matched.

In November 2020, Othram Inc., a exclusive lab in The Woodlands, Texas, that specializes in genome sequencing for regulation enforcement, reached out to market Murga and also her team that is services. There was still the problem of the price of the testing, however.

That’s whereby Las las vegas entrepreneur and also philanthropist Justin Woo came in. Woo, the founder that the nonprofit organization Vegas Helps, donated $5,000 to assist Othram and also the police department deal with a cold situation that had little DNA proof to work-related with.

“Stephanie’s situation was preferred specifically due to the fact that of the minimal amount of DNA evidence that to be available,” Spencer said.

Watch the July 21 news conference in the situation below.


Detectives sent the scant DNA proof they had actually left to Othram, wherein forensic researchers spent the following seven months using the company’s genome sequencing technique to build a hereditary profile the the alleged killer.

“The Othram family tree team provided the file to construct investigative leads the were went back to LVMPD,” a news release from the firm stated.

The leads eventually led to Marchand.

From vacation last week, Woo congratulated Othram’s scientists and Las vegas cold instance investigators on resolving the case.

“What’s much better than vacationing in Greece? This!” Woo wrote on Facebook.


Woo told the las Vegas sunlight that a friend had actually introduced him come David Mittelman, founder and CEO the Othram. Impressed v the company’s mission, he chose to money the experimentation in a ras Vegas-area cold case from his own pocket.

“It’s yes, really such a sad case, and also we’re happy that we could help with it,” Woo called the newspaper.

Marchand, that was 23 years old when Stephanie Isaacson to be murdered, had previously to be arrested in the Feb. 27, 1986, strangulation homicide the Nanette Vanderburg, 24, of ras Vegas. Details that that situation were no available, yet authorities claimed the case against Marchand was later dismissed because that a absence of evidence.

There to be DNA proof in Vanderburg’s killing, yet testing was not yet available.

The brand-new testing that connected Marchand to Stephanie’s murder additionally linked him come Vanderburg’s death.

“Marchand’s DNA native the case involving Nanette was compared to the DNA located in Stephanie’s case, and also it was a match,” police officials said.

It was unclear how detectives initially tied Marchand come Vanderburg’s death in 1986, however Spencer claimed there is no way to know if that knew Stephanie before the job of her murder.

“It shows up to it is in a random assault while she to be walking to school,” the sublievenant said.

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The slain teen’s family members has several of the answers they’ve sought because that so long, but the male accused the killing her will never be held criminally responsible.

“It’s great to have some closure, yet there is no justice for Stephanie in ~ all,” her mother’s explain read. “We will never have complete closure because nothing will ever carry my daughter earlier to us.”