Core Viewpoint - The article discusses the rising prevalence of autism and explores the underlying reasons for this increase, emphasizing that the rise is largely attributed to improved diagnostic practices rather than an actual increase in cases [3][6][16]. Summary by Sections Increase in Autism Diagnosis - The prevalence of autism has risen significantly, with the rate in the U.S. increasing from 1 in 150 children in 2000 to 1 in 31 children by 2022 [5][18]. - This trend is not limited to the U.S.; other high-income countries like the UK, Denmark, South Korea, and Japan have also reported similar increases [8]. Factors Contributing to Increased Diagnosis - Changes in diagnostic criteria over the years have led to more individuals being classified as autistic. For instance, the DSM and ICD have broadened their definitions, allowing for a wider range of symptoms and age groups to be included [12][14]. - A study indicated that approximately 60% of the increase in autism prevalence in Denmark from 1980 to 1991 could be attributed to changes in diagnostic standards [13]. - Increased awareness and reduced stigma around autism have led to more parents seeking diagnoses for their children, especially as educational support becomes more accessible [14][15]. Current Autism Prevalence Estimates - The U.S. Autism and Developmental Disabilities Monitoring Network reported that 1 in 31 children are diagnosed with autism, but some researchers question the accuracy of this data [18]. - A global estimate from 2021 suggested that the prevalence of autism spectrum disorder is approximately 1 in 127 individuals, totaling around 62 million people [18]. Genetic and Environmental Factors - Genetic factors are believed to play a significant role in autism, with a study estimating the heritability of autism at around 80% [22]. - Environmental factors are thought to have a smaller impact, with some studies linking advanced parental age and prenatal exposures to increased autism risk [23][24]. - Research indicates that there is no single environmental factor that significantly influences autism, and the interaction between genetic and environmental factors remains complex [25]. Research Initiatives and Funding - The NIH's Autism Data Science Initiative aims to explore the causes of autism and the effectiveness of existing interventions, focusing on the interaction between genetic and environmental factors [27]. - However, there are concerns about funding cuts to autism research, which have decreased from $274 million in early 2024 to $212 million in early 2025 [27].