"Yes, this is the problem the Professor gave me. Our research on Tong Yongqian's project has encountered a problem. His mother's X chromosome carrying the diseased gene has been tested and confirmed not to be from his maternal grandfather. Since it isn't from his grandfather, it must be from his grandmother. This way, we can infer that his grandmother's X chromosome also carries the same diseased gene. So, this diseased gene did not fall off his grandfather's Y chromosome."
"With this, everything becomes clear. The entire genetic lineage from Tong Yongqian's grandmother's side is explained flawlessly."
"Our hypothesis of Y and X gene recombination has been destroyed, what a pity."
"When I reported to the Professor then, after looking through the genetic test data I provided, he threw this question at me, saying I should only look for him after I figured it out. He said it is a simple problem but also a profound logical problem."
