Salk Team Breeds Strain of Mice to Aid Study of Rare Eye Disease

A team of scientists led by Salk Institute researchers has developed a genetically engineered strain of mice that will aid in the study of how to treat retinoblastoma, a rare inherited cancer that destroys the eyes of young children.

Dr. Pamela Mellon, an assistant professor at the Salk Institute and a lead researcher on the project, said that until now, retinoblastoma has only been observed in humans. By creating a strain of mice that exhibits the tumors, she said, researchers hope to greatly increase their knowledge of how to treat them.

“We’re hoping to develop therapies,” said Mellon. Currently, the only treatment is to surgically remove the affected eye, she added. “In the past, it’s been very difficult to contrive ways to test such things. You can’t do things to children that you can do to mice.”

Until now, she said, although about 200 new cases of retinoblastoma were detected in children each year, no other animals were found to exhibit retinoblastoma. But recent microscopic examination of the tumors in the genetically engineered mice revealed that they have exactly the same characteristics as human tumors, so Mellon said she has high hopes that continued research will apply to the treatment of affected children.

Mellon said she does not yet know what new therapies will be tested on the mice.

“But this is the first step to being able to try things,” she said. Mellon said the study of retinoblastoma in mice could have applications for other types of heritable cancers as well. Cancer researchers believe that most human cancers can occur in a heritable form.