yeah I was gonna say, I think the exact causes of ASD and autism in general are pretty controversial and somewhat unsettled, particularly the exact way genetics plays a role, and which genes are most likely to be responsible, so unless there’s been some very recent major breakthrough, “30% of ASD cases are caused by de novo mutations” seems a really bold claim, considering that would make de novo mutations one of the most significant contributing causes by far, and at least last I heard, the exact genetic causes of autism were not that settled (and heritable genes were more often thought to play a large role in at least certain types of cases). The former, more conservative claim seems a lot easier to swallow.