Preclinical Study and Lack of Causal Inference
The authors explicitly state this is a 'preclinical study' and that 'the causality of the gene-brain-behavior relationships cannot be established based on our results alone'. This means the findings, while promising, need further clinical validation and cannot yet claim direct cause-and-effect.
Ascertainment Bias in Study Population
The autism patients in the study were recruited from clinics, which may not represent the full spectrum of autism. Healthier individuals or those with more severe illness might be underrepresented, potentially skewing the findings regarding the impact of CNV.
Age Differences Between Cohorts
Deletion carriers were generally younger than duplication carriers and controls. Although efforts were made to age-match, this difference could not be completely eliminated and might introduce a confounding variable.
Focus on a Single Genetic Locus
The study focused on one specific genetic locus (16p11.2 CNV). While this allows for in-depth analysis, it limits the immediate generalizability to the broader genetic heterogeneity of autism and does not assess complex interactions with other genes.
Generalizability of Behavioral Associations
The association between TBM scores and articulation disorders was studied within a genetically stratified cohort. The authors suggest that investigating this relationship in a broader, non-genetically stratified autism population is warranted to ensure broader applicability.