FAAH and Tremor: This gene is expressed in the brain and has been implicated in X-linked recessive neuropsychiatric disorders.47 Functional studies in patient-derived fibroblasts have shown that variants in FAAH2 can reduce enzymatic activity, while affected individuals exhibit neurological features including motor impairment, gait abnormalities, and tremor.47 Inhibition of the FAAH enzyme has been shown in preclinical models to improve parkinsonian motor symptoms,48 highlighting the potential functional relevance of the FAAH2 variants identified in this study.