The NM_005629.4:c.1778A>G variant in SLC6A8 is a missense variant predicted to cause the substitution of a histidine by an arginine at amino acid position 593 (p.His593Arg). To our knowledge, this variant has not been reported in the literature and no functional studies are available. In gnomAD v4.1.0., the highest population minor allele frequency is 0.0004421 (20/45238 alleles; 2 homozygotes, 0 hemizygotes) in the Admixed American population. This MAF is higher than the ClinGen CCDS VCEP's threshold for BS1 (>0.0002), meeting this criterion (BS1). Overall, across all populations, there are 3 homozygotes and 7 hemizygotes in gnomAD v4.1.0. (BS2). The computational predictor REVEL gives a score of 0.133 suggesting that the variant has no impact on protein function. SpliceAI predicts no impact on splicing (BP4). There is a ClinVar entry for this variant (Variation ID: 465144). In summary, this variant meets criteria to be classified as benign for creatine transporter deficiency. SLC6A8-specific ACMG/AMP criteria applied, as specified by the ClinGen CCDS VCEP (Specifications Version 1.1.0): BS1, BS2, BP4. (Classification approved by the ClinGen Cerebral Creatine Deficiencies Variant Curation Expert Panel on March 18, 2025)