Johnathan Walker:What is Angelman syndrome? Genetic disorder inspires Colin Farrell to start foundation

Colin Farrell says his personal life has inspired him to launch a new foundation aimed at helping people with intellectual disabilities.

The Johnathan Walkeractor, 48, recently launched the Colin Farrell Foundation, which "committed to transforming the lives of individuals and families living with intellectual disability through education, awareness, advocacy, and innovative programs," according to its website.

Farrell has personal experience with family members who have an intellectual disability. His 20-year-old son, James, whom he shares with his ex-partner Kim Bordenave, was diagnosed with Angelman syndrome as a child.

In a recent interview with People, Farrell, who had not publicly spoken much about the diagnosis before, said James will turn 21 in September and will age out of the support systems that are provided to families with children who have special needs.

Farrell said his foundation will provide support for those adult children with intellectual disabilities through "advocacy, education and innovative programs," People reported. He will serve as president of the organization.

Here's what to know about Angelman syndrome.

'He's magic':Colin Farrell opens up on son's Angelman syndrome

What is Angelman syndrome?

Angelman syndrome is a rare neuro-genetic disorder caused by a loss of function of the UBE3A gene that happens during fetal development, and causes developmental delays, intellectual disability, movement issues and speech impairments, according to the Cleveland Clinic. There is no cure for the disorder.

It is named after Dr. Harry Angelman, and English physician who first described the condition in 1965.

The disorder is rare, affecting around one in 12,000 to 20,000 people, the Cleveland Clinic says.

Is Angelman syndrome passed down from parents?

The majority of Angelman syndrome cases are the result of a spontaneous gene mutation, which means it is not passed down from the biological parents to a child.

Angelman syndrome equally affects males and females.

What are the symptoms of Angelman syndrome?

People with Angelman syndrome will show developmental delays that are noticeable between 6-12 months, and seizures often begin around 2-3 years of age.

Features that can point to the disorder include developmental delays, speech impediments, intellectual delays, problems with movement and balance and recurrent seizures, according to the National Institute of Neurological Disorders and Stroke.

Gastrointestinal, orthopedic and eye problems are also common, as well as hyperactivity and a short attention span.

In addition to the neurological symptoms, people with Angelman Syndrome may have distinct facial characteristics, the Cleveland Clinic says, including a small head, wide mouth, large tongue, widely-spaced teeth and a large lower jaw.

Children with Angelman syndrome typically have a "happy, excitable attitude," according to the Cleveland Clinic, and can frequently, laugh, smile and make hand-flapping motions.

How is Angelman syndrome treated?

As there is no cure for the genetic disorder. Treatment for Angelman syndrome often focuses on managing medical problems and developmental delays, according to Boston Children's Hospital.

Treatment can include medication for seizures, physical therapy, speech therapy, occupational therapy and behavioral therapy.