The NM_005629.4:c.1145C>T variant in SLC6A8 is a missense variant predicted to cause substitution of Proline for Leucine at amino acid 382 (p.Pro382Leu). This variant is absent from gnomADv2.1.1, and has been reported in two individuals in the literature. In one affected individual in the literature, the ratio of urine Creatine to Creatinine was >99th percentile of normal, and reduced creatine uptake in patient fibroblasts was reported. In silico predictor REVEL suggests this variant will have a damaging / pathogenic effect on the protein (score=0.906). There is a ClinVar entry for this variant (Variation ID: 533700, 1 star review status) with 5 submitters classifying the variant with conflicting interpretations (Pathogenic(3); Likely pathogenic(1); Uncertain significance(1)). In summary, this variant meets the criteria to be classified as Likely Pathogenic for Creatine transporter deficiency based on the ACMG/AMP criteria applied, as specified by the ClinGen Cerebral Creatine Deficiency Syndromes Variant Curation Expert Panel (Specifications Version 1.0): PP4_Strong, PM2_Supporting, PP3.