NYPD forms unit to solve crimes with new DNA technique used in Gilgo serial killer case 

A newly formed NYPD unit solved a more than 20-year-old pattern of rape cases by using investigative genetic genealogy, an up and coming forensic method being used with success in identifying some of the Gilgo Beach murder victims, officials said Thursday.

“The case we are talking about is a perfect investigation,” said NYPD deputy chief Brian McGee, head of the department’s forensic investigations division, at a news conference announcing the arrest of a Florida man in connection with two rapes: one of a 27 year-old Manhattan woman in her Midtown apartment in May 2000 and another of a 21 year-old Bronx woman in December 2001.

McGee said the investigation moved quickly over a nearly six-month period after genetic genealogy helped break the case. Initially, DNA recovered from rape kits couldn’t be matched to any known convicted offender in the law enforcement CODIS system. The genetic samples showed that the same suspect was involved in both rapes, said McGee.

NYPD investigators turned to a new team of investigators within the department using genetic genealogy, said McGee. Once used mostly by people trying to find long lost relatives, the technique allows for investigators to compare unknown suspect DNA with genetic profiles used in the relative searches whose profiles are in certain consumer DNA databases.

While McGee said the NYPD genetic genealogy unit is the first for a police agency in the state, the FBI has a similar unit involving agents nationwide. Special agent Laurie Giordano, one member of the FBI team, has used investigative genetic genealogy to identify two Gilgo Beach victims, Valerie Mack and Karen Vergata. 

FBI investigators are using genealogy in an effort to identify three other unidentified Gilgo victims: a woman known as “Peaches” because of her tattoo, her toddler daughter and an Asian man.

While stringent New York State rules had previously prohibited police agencies from using investigative genetic genealogy, changes in the last couple of years permit police in the state to use two private laboratories to develop DNA profiles fit for genealogical study, noted McGee. Parabon NanoLabs was the approved lab used in the rape case.

Charged with first-degree rape was Jancys Santiago, 48, formerly of the Bronx and now living in Groveland, Fl., Bronx District Attorney Darcel D. Clark said in a prepared statement. Santiago was arrested coming out of his Florida home and was extradited to New York City last month, said officials. Santiago, a married father with children, was arraigned on the Bronx case on Nov. 15, Clark said. In the Manhattan rape case Santiago was arraigned on Nov. 9 and ordered held without bail, noted Clark.

The DNA profile used to do genetic searching in specialized databases meant that Linda Doyle, a genetic genealogist who has worked in the past with Dr. Colleen Fitzpatrick of Identifinders Inc., of California, could construct a family tree that focused the probe on Santiago, explained McGee. Investigators then got an abandonment sample of Santiago’s DNA from a water bottle he had discarded and confirmed his identity as a viable suspect, according to McGee.

According to McGee, the arrest of Santiago is the first use in the state of investigative genetic genealogy to solve a sex case. In November 2022, in what appears to be the first genetic genealogy case in the state, a 75-year-old Queens man was sentenced to 20 years in prison for the 1976 murder of 81-year-old World War I veteran George Seitz, whose remains were found buried in the backyard of a home in Richmond Hill.

By Anthony M. DeStefano

tony.destefano@newsday.comtonynewsday

Anthony M. DeStefano has been a reporter for Newsday since 1986 and covers law enforcement, criminal justice and legal affairs from its New York City offices.