SLC6A3 encodes the dopamine transporter (DAT), which mediates sodium- and chloride-dependent reuptake of dopamine from synapses, playing a crucial role in dopaminergic neurotransmission. The transporter regulates dopamine levels by removing dopamine from the synaptic cleft, terminating dopaminergic signaling. SLC6A3 contains a 40-bp variable number tandem repeat (VNTR) polymorphism that has been extensively studied in neuropsychiatric disorders 1. Meta-analyses have revealed associations between specific SLC6A3 polymorphisms and personality disorders in European populations, particularly the 9-repeat allele variant 2. However, the relationship between SLC6A3 variants and schizophrenia remains inconsistent, with some studies showing associations with specific SNPs while others find no significant correlations 13. In ADHD research, differential associations have been observed between childhood and adult forms of the disorder, with the 9/9 genotype and 9-6 haplotype associated with persistent ADHD, contrasting with childhood ADHD patterns 4. Importantly, meta-analyses have failed to demonstrate significant associations between SLC6A3 VNTR polymorphisms and striatal dopamine transporter availability measured by SPECT imaging 5, suggesting the functional mechanisms underlying these genetic associations require further investigation.