MFSD8
Chr 4ARmajor facilitator superfamily domain containing 8
Also known as: CCMD, CLN7, SLC74A1
The encoded protein functions as an outward-rectifying chloride channel that maintains endolysosomal chloride homeostasis, regulates lysosomal calcium content by activating TRPML1 channels, and contributes to progressive acidification from endosome to lysosome. Mutations cause neuronal ceroid lipofuscinosis type 7 (variant late infantile-onset) and macular dystrophy with central cone involvement through an autosomal recessive inheritance pattern. Disease results from loss-of-function mutations that disrupt endolysosomal membrane function and ion homeostasis.
Definitive — sufficient evidence for diagnostic panels
Population Genetics & Constraint
gnomAD v4 — loss-of-function & missense intolerance
Highly tolerant — LoF variants common in population
Mild missense constraint
Lysosomal membrane transporter. Biallelic LOF causes CLN7 (variant late-infantile neuronal ceroid lipofuscinosis). This is an autosomal recessive LOF gene.
Predictions shown for reference only — model trained on dominant genes, not applicable to AR conditions.
The Badonyi & Marsh prediction model was trained exclusively on dominant disease genes. Predictions are not reliable for genes with autosomal recessive inheritance and are shown at reduced opacity for reference only.
Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.
ClinVar Variant Classifications
0 submitted variants in ClinVar
Protein Context — Lollipop Plot
MFSD8 · protein map & ClinVar variants
Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.
3D Protein StructureAlphaFold
External Resources
Links to major genomics databases and tools
Clinical Trials
Active and recruiting trials from ClinicalTrials.gov
Study for the Treatment for CLN7 Disease
ACTIVE NOT RECRUITINGNatural History and Longitudinal Clinical Assessments in NCL / Batten Disease, the International DEM-CHILD Database
RECRUITINGExternal Resources
Links to major genomics databases and tools