Eyes of Two Mummies Restored in California Lab

John Roach
for National Geographic News

October 24, 2005

A team of scientists in California has restored the eyes of two Chilean mummies and plans to use them to investigate ancient diseases.

One eye came from the mummified remains of a two-year-old boy who died a thousand years ago. The other eye belongs to a 23-year-old woman who died about 750 years ago. Both bodies were naturally preserved in Chile's arid Atacama Desert.

The mummy tissues resemble freeze-dried material and lack the chemical preservatives used in Egyptian mummies, said William Lloyd, an ophthalmologist at the University of California at Davis Medical School who is leading the restoration.

Huck Holz, one of Lloyd's colleagues at the school, convinced Lloyd to pursue the project after he read a profile of Arthur Aufderheide in the May 16 issue of the New Yorker magazine.

Aufderheide is a renowned paleopathologist—a scholar of ancient diseases—at the University of Minnesota at Duluth. He salvages and studies mummy organs from around the world.

In the magazine profile, Aufderheide said he had conducted the original autopsy on the mummies and was saving the eyes for the right investigator.

Holz thought Lloyd had the right experience for the task and persuaded him to contact Aufderheide.

"It sounded like they had lots of experience, so … I agreed to work with them," Aufderheide said.

Rehydrated Eyes

Earlier this month the mummified eyeballs arrived at Lloyd's lab. "They looked like a cheese doodle—very lightweight, very delicate," he said.

"[Last] Monday we began the process of attempting to bring these ancient specimens into the 21st century, so we can use modern pathology methods to examine them," he said.

The first step in the process is rehydration of the dried-up cells. When the team started, the eyes had a dry and brittle texture. Now they are restored to nearly the size and consistency of normal human eyes, Lloyd said.

The team was able to identify certain tissues that clearly belong to the eye, such as muscles and a lens. These parts are distinguishable from other body parts, such as bits of skin and eyebrow hair.

Next the team prepared the eyes for examination—a process that involved embedding the eyes in paraffin wax, slicing them for viewing under a microscope, and applying stains to highlight the tissues.

The team was able to identify specific structures inside the eyes. The two-year-old boy's eye was badly decomposed, but the lens was intact. The woman's was "remarkably well preserved," Lloyd said.

"There were portions of that eye that looked like they were just out of the operating room down the hallway, and this is from 750 years ago," he said. "It tells us we are on the right track to successfully rejuvenate these tissues."

Eye Exam

Aufderheide's previous research on the mummies' bodies revealed that they both suffered and recovered from bouts of pneumonia.

The boy also had an inherited liver disease. The woman had lice, bad teeth, and osteoporosis—a decalcification of the bones. A likely explanation for the condition, Aufderheide said, was a diet of plants rich in oxalates, compounds that interfere with calcium absorption.

Lloyd said his team hopes to use the eyes of the mummies to diagnose other diseases, applying the same techniques used in autopsies today.

"What types of disease affected these cultures, and are they similar or different to what we see today?" Lloyd said. "Not just cataracts and glaucoma, but what about diabetes, high blood pressure, infectious diseases?"

According to Aufderheide, the signature of various diseases is readily apparent in the eyes.

"For example, high blood pressure changes the arteries, and that is reflected when you look in the eye of a living person," he said.

Since arteries tend to be well preserved in mummies, Aufderheide said the chances are high for the signature of diseases such as diabetes and hypertension to survive for hundreds of years.

Lloyd said finding the signature of these diseases in people that lived in the Americas before the time of Columbus would show that such ailments are ancient, and that genetics—not the modern environment or diet—may be their primary cause.

"It would be very cool to identify changes in the eyes of mummies that provide examples of these diseases a thousand years ago," he said.

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