I don't know what happened. I watched XMFC and got inspired to revamp 'One Art', and then young Charles wanted to be in it, and then he was flirting, and I think this might end up being Methos/Charles... IDEK.

Also, everything I know about genetics I learned from Wikipedia.

About fifty years ago

Charles didn't notice it at first. He blamed the presence, like a static whine at the back of his mind, on the mass of students, on his anxiety at presenting his first lecture series, but it didn't decrease, not even when he found his stride and many of the students, as is the nature of students attending early morning lectures, stopped attending. Eventually, he pinpointed it to a man who always sat in the back row. The man listened intently, and seemed to follow easily, but he never asked questions and he never stuck around long enough for Charles to track him down.

Even when Charles brushed cautiously against his mind, the static remained. It prickled like pins and needles against his consciousness until he lost his train of thought. The man didn't seem to notice the intrusion and Charles decided that his mental defences must be instinctive and resilient. Charles contemplated, only theoretically of course, what it would take to bring them down.

It's only on the last day of his lecture series that the man approaches him. Charles can't tell how old he is; he might be a few years older than Charles, but there's also a sense of timelessness to his appearance.

"Doctor Xavier," he greets, and his voice is smooth and accented in a way Charles can't quite place.

"I'm John White." A non-descript name and Charles sensed truth, but with a curious mixture of something else, too. Not quite deception, but something close. He's a mystery and Charles loves mysteries.

"Just Charles, please."

"Charles, then," John conceded with a brief smile. "I'm curious as to whether you believe the mutations you speak of have already manifested."

"It wouldn't surprise me," Charles hedged. John seemed keenly interested, more so than just a passing curiosity, and Charles wished he could read his mind to see if he had a mutation of his own. "Mutations are occurring all the time. Even your hazel eyes are a mutation of the OCA2 gene. And it's a very groovy mutation."

"Is that so?" John asked as he leaned forward with a faint smirk. Charles smiled as he looked up at him.

"You also have a very groovy HMGA2 gene."

...

The next time Charles senses that intriguing mind, it's over 40 years later. Charles has been kidnapped and John is standing at Stryker's shoulder, gaze blank.