I spontaneously decided to re-examine the genetics of Ultra Instinct, specifically how it relates to Daniel, trying to figure out if the gene is dominant or recessive. And I kept running into the paradox of 'if X is true, it has to be dominant', 'if Y is true, it has to be recessive'. (For example, if it's dominant, how were 9 children born without it, etc.)
To reconcile this paradox, I even started considering the possibility that Daniel's dad is not his dad and he is part Yamazaki (it's possible...). But then I realized something.
Daniel's UI is different than the Yamazakis'. He wasn't born with it.
And I remembered something I learned a long time ago: for people with autoimmune disorders, they are not typically born with them, they are born with a predisposition and the onset of the disease is triggered later in life.
What if Ultra Instinct functions similarly to autoimmune disorders where a person can have a predisposition and trigger it much later? That would explain Daniel triggering it despite presumably not being related to Gun. It would mean much more people are genetically predisposed but most of them, like Daniel's parents, never go on to trigger it. And for the Yamazaki clan, it somehow became congenital.
