A new study has found that Hispanic families in the Southwest are likely to have a gene mutation that causes blindness.

If your family has the rare eye disorder retinitis pigmentosa, you probably already know because of a history of blindness.

This study from the University of Texas School of Public health in Houston found that 36 percent of Hispanic families with the disease, including in Arizona, have a dominant form of the gene that causes it.

The finding, according to senior author Steve Daiger, could mean one person from a colonizing country or Mexico developed that gene and brought it to Arizona.

“We immediately had people from Spain, and Mexico and Brazil saying, they will send us samples," he said. "So we’re right in the process now of trying to discover, is this found in Spain, is it found in Mexico, might it be found elsewhere in South America and Latin America.”

He said the Southwestern Hispanic families, including in Arizona, have this version of the disease because of one single person.

“Somebody living two centuries ago, three centuries ago, perhaps in the Southwest United States, perhaps Mexico, perhaps even in Spain, had this mutation. And by just the standard way that people migrate and those families spread, this particular mutation increased with time," Daiger said.

The disease shows up in teenage years, starting with poor peripheral vision and can lead to blindness. Daiger suggests anyone who suspects they have the disease get genetic testing to see what they can do to treat it.