Final answer:
Fragile X syndrome is considered one of the single-gene causes of autism, making the statement true.
Step-by-step explanation:
True or False: Fragile X syndrome is the number one single-gene cause of autism.
The statement is believed to be true. Fragile X syndrome is indeed one of the most well-characterized, single-gene causes of autism spectrum disorder (ASD). While the exact causes of ASD are largely unknown, identified genetic forms like Fragile X and Rett Syndrome have been linked to the condition. Autism spectrum disorders are complex and involve multiple genetic factors, which can vary significantly among different individuals. It is also crucial to note that, despite some misconceptions, vaccines have no proven connection to the development of autism.