On May 18, 2020, the NIH reported that roughly 3 to 5% of children with an aunt or uncle with autism spectrum disorder (ASD) can also be expected to have ASD, compared to about 1.5% of children in the general population. Researchers also found that a child whose mother has a sibling with ASD is not significantly more likely to be affected by ASD, compared to a child whose father has a sibling with ASD. The findings call into question the female protective effect, a theory that females have a lower rate of ASD than males because they have greater tolerance of ASD risk factors.