SLC6A3 gene polymorphisms are associated with striatal dopamine transporter changes after glucose loading

Area of Science:

• Neuroscience
• Genetics
• Pharmacology

Background:

• Dopamine transporter (DAT) availability is crucial for neurotransmission.
• Glucose metabolism can impact brain function.
• The SLC6A3 gene encodes the DAT.

Purpose of the Study:

• To investigate the association between SLC6A3 gene polymorphisms and dopamine transporter (DAT) availability changes after glucose loading.
• To determine if specific SLC6A3 genotypes modulate the effects of glucose on DAT binding potential.

Main Methods:

• 38 healthy male participants underwent PET imaging with 18F-FP-CIT after glucose or placebo infusion.
• SLC6A3 gene polymorphisms (VNTR, rs2652511, rs2937639) were genotyped.
• DAT availability was quantified as binding potential (BPND) in brain regions.

Main Results:

• A subset of participants (n=6) with a specific combined genotype (rs2652511 CT/rs2937639 AG) showed higher caudate nucleus and putamen BPND after glucose loading compared to placebo.
• No significant differences in BPND were observed in the ventral striatum (VST), caudate nucleus, or putamen based on genotype overall.
• Alleles for rs2652511 and rs2937639 were inherited in fixed combinations (C-G or T-A).

Conclusions:

• The SLC6A3 gene polymorphism is associated with changes in DAT availability following glucose loading.
• Specific SLC6A3 genotypes may influence the brain's response to glucose in terms of dopamine transporter availability.