jxyzptlk t1_j8a5l83 wrote

OP worded it poorly, here's the stuff (posting from phone so formatting might be off):

"Almost all Alzheimer’s disease patients younger than 30 have pathological gene mutations, according to the authors. To date, the youngest person known to have been diagnosed with Alzheimer’s disease was a 21-year-old who carried a gene mutation.

But the adolescent patient of the most recent study differed from previous young patients because no known genetic mutations were identified in the 19-year-old who was diagnosed in China."