I don't think finding a cure for deafness or blindness is monstrous.

Eva Kor was 10 years old when she arrived at Auschwitz, the Nazi death camp in Poland where 1.1 million people, nearly all of them Jews, perished in the Holocaust. On the selection platform, her mother held on tightly to Eva and her twin sister, Miriam...

“Twins?” an SS guard called out. “Twins?”

“Is that good,” Mrs. Kor remembered her mother inquiring, if her daughters are twins? The guard said yes, and the sisters were taken away. They would never see their mother or the rest of their family again.

Eva and Miriam were among 1,500 sets of twins subjected to medical experiments by the infamous Nazi doctor Josef Mengele. Fewer than 200 of those victims are thought to have lived.

The medical experiments conducted there and at other Nazi camps had three purposes, according to the U.S. Holocaust Memorial Museum: to improve medical treatment for German troops, to test new medical procedures and drugs, and to confirm Nazi views of the supremacy of the Aryan race.

Victims were subjected to extreme altitudes and temperatures, injected with pathogens and sterilized. They endured bone-grafting procedures and injections in their eyes to change their eye color. Many victims were permanently disfigured, sickened or weakened. Many more died.

“Everything in the world was done to me that would have killed me,” Mrs. Kor said years later in an interview, “and here I am alive.”

She recalled being stripped of her clothes and tied down by her arms as she endured repeated examinations lasting as long as eight hours. From one arm, her tormentors took blood. “They wanted to know how much blood a person can lose and still live,” Mrs. Kor said. In the other arm, she received injections, sometimes five at a time.

Once, she said, the experiments brought on a dangerously high fever.

“I was trembling,” Mrs. Kor told ABC News in 1999. “My arms and my legs were swollen, huge size,” with red patches. Mengele examined her, she said, and pronounced that she had two weeks to live.

Her sister, Miriam, sustained kidney damage so severe that her kidneys stopped growing; in 1987, Mrs. Kor donated a kidney to her.