Page 28 - ARUBA TODAY

A28 SCIENCE
Tuesday 20 February 2018
Medical examiner taps DNA science to find missing persons

By VERENA DOBNIK Unidentified Persons Sys-
NEW YORK (AP) — For fami- tem. The system is capable
lies who have searched of searching for unique sim-
years for missing loved ilarities in DNA strings that
ones, donating a sample indicate two people are
of their DNA is often a last, related.
desperate act to confirm "Our job is to help identify
their worst fears. your loved one and return
New York City's medical ex- them to you, no matter
aminer is leading a nation- where in the United States.
wide effort to collect ge- They don't have to have
netic material and match died here in New York City,"
it with unidentified human says Mark Desire, assistant
remains. It's a way to finally director of the medical ex-
give family members some aminer's Department of Fo-
answers and maybe some rensic Biology.
solace. Mary Lyall submitted her
"People will not rest with- DNA to the New York City
out answers, at least some medical examiner, along
answers," said Dr. Barbara with her husband's, as part
Sampson, the city's chief of her hunt for her missing
medical examiner. daughter.
Over the last decade, thou- In this June 4, 2010 file photo, a criminalist examines for DNA evidence at a lab in the NYC Office Suzy Lyall was 19 when
sands of DNA samples have of Chief Medical Examiner, Friday, June 4, 2010, in New York. she disappeared in 1998.
been donated to the city's Associated Press She was last seen on the
medical examiner's office. University at Albany cam-
Most include swabs of sa- and crossed the U.S. bor- One such advance, Samp- Pulverized genetic material pus getting off a bus. After
liva from close relatives, but der from Mexico. DNA son said, was learning how is spun in a centrifuge and she vanished, her mother
also DNA taken from items matched with the remains to get good genetic mate- turned into a clear liquid sifted through her room at
used by the missing per- of a 35-year-old "John Doe" rial out of bone fragments. that's poured into test tubes home looking for clues. In
sons themselves, including who succumbed to expo- DNA testing once required on a robotic assembly line. a wastebasket, she found
toothbrushes, combs, razor sure and dehydration in the a large sample of blood or The tubes are bar-coded a sanitary napkin Suzy had
blades and, once, even a Texas desert. saliva that was often de- and padlocked in metal wrapped and discarded
sanitary napkin. "It's sad," Merchan said. "We stroyed in the process. The cages in a secure vault. amid crumpled paper. Two
They've led to the identi- hoped Manuel would call latest genetic technology Genetic profiles developed decades later, no match
fication of about 50 miss- one day. But we at least allows a few cells to be from the tests are plugged has been made. "I still look
ing people each year, all know what happened." reproduced for DNA that into the databank called out the window and think,
of whom had been found On any given day, there lasts indefinitely. the National Missing and 'Where is she?'" Lyall said.q
dead. But for many who are as many as 100,000 ac-
in the U.S., according to Experts: Underwater archaeology
have submitted samples, tive missing-persons cases
the wait continues.
"Part of you hopes they the FBI's National Crime In-
never call you, because formation Center. Most of site imperiled in Mexico
if they call, that means it's those people are eventual-
over," said Rose Cobo, who ly found safe. The medical
submitted DNA to the pro- examiner's office program MEXICO CITY (AP) — Pol- the continent have been gest water levels may have
gram after her adult niece is open to people whose lution is threatening the found there, dating back briefly dropped in the 216-
vanished in 2016 after be- loved ones have been recently mapped Sac Ac- more than 12,000 years, mile (347-kilometer) -long
ing treated at a Brooklyn missing 60 days or more. tun cave system in the Yu- and now-extinct animal system during a drought
hospital for postpartum de- The New York City medical catan Peninsula, a vast remains push the horizon about 1,000 A.D. And some
pression following the birth examiner's office has been underground network that back to 15,000 years. He artifacts have been found
of a son. Chelsea Cobo's a pioneer in advanced experts in Mexico say could said researchers found a dating to the 1847-1901
whereabouts are still un- DNA techniques since 9/11, be the most important un- human skull that was al- Maya uprising known as
known. when it was tasked with derwater archaeological ready covered in rainwater the War of the Castes.
The program helped end using genetic evidence site in the world. Subaquat- limestone deposits long be- Humans there probably
Luis Merchan's quest to to identify and sort tens of ic archaeologist Guillermo fore the cave system flood- didn’t live in the caves, de
find his younger brother, thousands of small pieces de Anda said the cave sys- ed around 9,000 years ago. Anda said, but rather went
Manuel, who was report- of human remains found tem’s historical span is like- De Anda said over 120 sites down to them “during
ed missing in 2015 after in the rubble of the World ly unrivaled. Some of the with Maya-era pottery and periods of great climate
he left his native Ecuador Trade Center. oldest human remains on bones in the caves sug- stress, to look for water.”
Sac Actun is “probably the
most important underwa-
ter archaeological site in
the world,” he said. But de
Anda said pollution and
development may threat-
en the caves’ crystalline
water. Some of the sinkhole
lakes that today serve as
entrances to the cave sys-
tem are used by tourists to
snorkel and swim. q