"In 1967, I started seeing spots," says the 68-year-old Iowa father and grandfather. "I was around 20 when the hemorrhaging started."
Jackson would eventually be diagnosed with the rare genetic eye disease Autosomal Dominant Neovascular Inflammatory Vitreoretinopathy (ADNIV), which eventually causes blindness in those who carry the gene.
Sadly for Jackson, he and many members of his family did: Of the approximately 123 diagnosed cases in the U.S., 84 are in the Jackson family bloodline, dating back to the early 1800s.
Recalls Jackson of his initial diagnosis: "The retina was swelling, and these small vessels would grow out like a clump of grapes at the end. [Doctors] say it was a weak point for hemorrhaging. ... It was a slow progression. I don't see anything any more."
Unfortunately, his daughters, Shawnna Williamson and Shannon Jackson Enke, are also going blind.
"My dad blamed himself at first … he kept saying, 'I'm sorry,' " Williamson says after she was diagnosed, before telling him, "It's not your fault, dad."
Now, Jackson's grandchildren have a 50-50 chance of going blind, as well.
Some want to know, while others do not.
"I've decided not to get tested," says 22-year-old Skyler Howard. "I'm living every day to every day."
Kolton Enke, 18, however, "would like to know if I'm going to lose my eyesight, so I can do certain things before I go blind." He has been tested and is expecting the results any day now.
Jackson's granddaughter, Bobbi Boline, 25, learned she has the gene. She tries to reassure herself. "I watched my grampa go through it, and I'm okay with it … I am."
But if the Jacksons have passed down blindness from one generation to the next, they also have learned all about courage and resilience from strong-willed and optimistic Jerry Jackson, a bicycle mechanic and avid cyclist – who rides tandem bikes with sighted riders.
He has also led the family's effort to help researchers at the University of Iowa, the only institution studying ADNIV, to find a cure, according to USA Today.
"I'm the only kid in school who's got a blind grampa, and he builds bicycles," Howard says he realized when he got older. "That’s pretty cool."
Despite the challenges his family faces, Jackson remains hopeful.
"They could find a cure for the eye disease by implanting a chip behind the retina," he says. "If that happens, that can make a cure for a lot of different eye diseases."
Reporting by CATHY FREE