A Minneapolis businessman charged Friday with possession of child pornography is suffering from a debilitating brain disease that leads to changes in behavior, his family said.

Gregory Matthew Dolphin, 62, was charged with a single felony count, but the investigation continues, according to the Hennepin County attorney's office. He is jailed in lieu of $100,000 bail and is expected to make his first court appearance Monday.

Dolphin retired as CEO of Dolphin Fast Food, a multiunit Burger King franchisee and a property of the Dolphin Group Cos., when all the restaurants were sold last year, said spokesman Thomas Dolphin.

Thomas Dolphin said in a statement that Greg Dolphin received a Mayo Clinic diagnosis last June of "frontotemporal degeneration, a progressive brain disease that can result in changes in personality, impaired judgment and impulsive behaviors."

"Since that diagnosis, the Dolphin family has taken steps to assist Greg in his care," Thomas Dolphin wrote. "Obviously, we are shocked and saddened by these allegations involving his personal behavior."

More than a third of people with frontotemporal dementia (FTD) act out criminal behaviors, including theft, traffic violations (with or without the influence of drugs or alcohol), violence and hypersexuality, according to a March 2015 study published in JAMA Neurology, a medical journal published by the American Medical Association.

Greg Dolphin remains a minority shareholder in some of the Dolphin operating companies (including a diversified collection of mercantile ventures, such as Dolphin Staffing, 21st Century Bank and various real estate holdings). However, he does not have a management role, Thomas Dolphin said.

Dolphin's mother, Dorothy Dolphin, founded the agency and other businesses. He is the nephew of the late billionaire Carl Pohlad, who owned the Twins.

"The allegations involving Greg are personal in nature, do not involve the Dolphin companies and will not impact the operations or financial strength of the various Dolphin companies," Thomas Dolphin said. "As a company, we are conducting our own investigation and cooperating with the authorities.

"As his family, we will provide Greg with our loving support and whatever additional assistance he may need. We would ask that people respect the family's need for healing at this time."

According to the criminal complaint:

Minneapolis police received multiple mandatory cybertips from social media companies that Dolphin was using their programs to acquire or distribute child pornography. Based on those tips, police obtained search warrants on Dolphin's devices, home and office. When police arrived at Dolphin's home just north of Lake Calhoun on Thursday, he was in his vehicle with a packed suitcase. Police pulled him out of the car and arrested him.

After obtaining a search warrant, officers confiscated a cellphone, two flash drives he was carrying and his computer.

Police began reviewing his devices and one video was discovered showing a juvenile girl being sexually abused. The names on other files referenced pedophilia and other search terms related to child pornography. The examination is continuing, charges said. In an interview with police, Dolphin allegedly admitted he knew there was child pornography on his computer.

Twitter: @KarenAnelZamora