Related Experiment Video
Updated: Jul 15, 2026

Targeted Next-generation Sequencing and Bioinformatics Pipeline to Evaluate Genetic Determinants of Constitutional Disease
Published on: April 4, 2018
Functional characterization of missense variants in the creatine transporter gene (SLC6A8): improved diagnostic
Efraim H Rosenberg1, Cristina Martínez Muñoz, Ofir T Betsalel
1Department of Clinical Chemistry, Metabolic Unit, VU University Medical Center, Amsterdam, The Netherlands.
Abstract:
Creatine transporter deficiency is an X-linked mental retardation disorder caused by mutations in the creatine transporter gene (SLC6A8). So far, 20 mutations in the SLC6A8 gene have been described. We have developed a diagnostic assay to test creatine uptake in fibroblasts. Additionally, we expanded the assay to characterize novel SLC6A8 missense variants. A total of 13 variants were introduced in the SLC6A8 cDNA by site-directed mutagenesis. All variants were transiently transfected in SLC6A8-deficient fibroblasts and tested for restoration of creatine uptake in deficient primary fibroblasts. Thus, we proved that nine variants (p.Gly87Arg, p.Phe107del, p.Tyr317X, p.Asn336del, p.Cys337Trp, p.Ile347del, p.Pro390Leu, p.Arg391Trp, and p.Pro554Leu) are pathogenic mutations and four variants (p.Lys4Arg, p.Gly26Arg, p.Met560Val, and p.Val629Ile) are nonpathogenic. The present study provides an improved diagnostic tool to classify sequence variants of unknown significance.
Related Concept Videos
Pharmacogenetics of Drug Transporters: P-Glycoprotein and Solute Carrier Transporters
Glucose Transporters
Facilitated diffusion-glucose transporters (GLUTs) are encoded by the solute-linked carrier (SLC) family 2, subfamily A gene family, or SLC2A. The 14 GLUT protein members are distributed into three classes:
Pharmacogenomics: Identification of New Drug Targets
The Significance of Membrane Transport
Transporters facilitate either an active or passive movement of solutes. They can allow a single-molecule transport down its...

