Seroatlas · Human Serome Atlas

FDFT1

Squalene synthase

Also known as: FDFT_HUMAN, SQS

Cross-references: UniProt · Ensembl · Human Protein Atlas · GeneCards · NCBI Gene

Protein identityUniProt · HPA

UniProt accession
P37268
Gene
FDFT1
Ensembl
ENSG00000079459
Chromosome
8
Canonical length
417 aa
Protein class
Disease related genes, Enzymes, Metabolic proteins, Potential drug targets, Predicted intracellular proteins, Predicted membrane proteins
Subcellular location
Endoplasmic reticulum

OverviewNCBI Gene

This gene encodes a membrane-associated enzyme located at a branch point in the mevalonate pathway. The encoded protein is the first specific enzyme in cholesterol biosynthesis, catalyzing the dimerization of two molecules of farnesyl diphosphate in a two-step reaction to form squalene. [provided by RefSeq, Jul 2008]

Canonical amino-acid sequenceUniProt

417 residues, UniProt reviewed canonical sequence.

>P37268|FDFT1
     1  MEFVKCLGHP EEFYNLVRFR IGGKRKVMPK MDQDSLSSSL KTCYKYLNQT SRSFAAVIQA
    61  LDGEMRNAVC IFYLVLRALD TLEDDMTISV EKKVPLLHNF HSFLYQPDWR FMESKEKDRQ
   121  VLEDFPTISL EFRNLAEKYQ TVIADICRRM GIGMAEFLDK HVTSEQEWDK YCHYVAGLVG
   181  IGLSRLFSAS EFEDPLVGED TERANSMGLF LQKTNIIRDY LEDQQGGREF WPQEVWSRYV
   241  KKLGDFAKPE NIDLAVQCLN ELITNALHHI PDVITYLSRL RNQSVFNFCA IPQVMAIATL
   301  AACYNNQQVF KGAVKIRKGQ AVTLMMDATN MPAVKAIIYQ YMEEIYHRIP DSDPSSSKTR
   361  QIISTIRTQN LPNCQLISRS HYSPIYLSFV MLLAALSWQY LTTLSQVTED YVQTGEH

LocalizationUniProt · AlphaFold · HPA

Whether an antibody against FDFT1 can act on the native protein depends on physical access: surface and secreted proteins are reachable by circulating antibodies, intracellular proteins usually are not.

Antibody reachability
Other membrane
Secreted
No
Transmembrane segments
2
Mean surface accessibility (rSASA)
0.25
Highest tissue expression
162 nTPM

Expression across tissuesHPA

Tissue

  • spinal cord: 162 nTPM
  • esophagus: 155 nTPM
  • skeletal muscle: 154 nTPM
  • salivary gland: 133 nTPM
  • skin: 122 nTPM
  • adrenal gland: 118 nTPM

Single-cell type

  • late primary spermatocytes: 236 nCPM
  • late spermatids: 165 nCPM
  • early spermatids: 158 nCPM
  • oocytes: 152 nCPM
  • oligodendrocytes: 137 nCPM
  • papillary tip epithelial cells: 83 nCPM

Immune cell

  • memory B-cell: 61 nTPM
  • basophil: 52 nTPM
  • naive B-cell: 46 nTPM
  • T-reg: 46 nTPM
  • total PBMC: 44 nTPM
  • myeloid DC: 29 nTPM

Brain region

  • medulla oblongata: 86 nTPM
  • white matter: 86 nTPM
  • pons: 71 nTPM
  • spinal cord: 55 nTPM
  • thalamus: 54 nTPM
  • cerebral cortex: 53 nTPM

DiseaseUniProt · ClinVar · IEDB · PubMed

Four sources answering four different questions about FDFT1.

Disease | AllUniProt

Conditions FDFT1 is implicated in, by any mechanism.

Disease | GeneticClinVar

5 pathogenic / likely-pathogenic of 168 ClinVar records.

Conditions with pathogenic or likely-pathogenic variants.

  • Squalene synthase deficiency

Genetic constraint and essentialitygnomAD · DepMap

Does the body need this protein intact? Low LOEUF or a strong DepMap dependency means loss or blockade of the protein is likely to be felt.

gnomAD LOEUF (loss-of-function intolerance)
1.58
gnomAD pLI
0
gnomAD missense Z
-3.88
DepMap mean gene effect
-0.15
DepMap dependency class
selective

Cancer expressionTCGA

Across TCGA tumor cohorts, this protein is over-expressed in roughly 4% of surveyed tumor types (aggregate summary; per-cohort expression, alteration, and survival load in the interactive view).

OntologyGO

Biological processes

Molecular functions

Cellular components

Protein domainsUniProt · Pfam · InterPro

KeywordsUniProt

Antibody and autoantibody relevanceSeroatlas analysis

Seroatlas reads FDFT1 as an antibody target. Whether an autoantibody or antibody against FDFT1 could matter depends on whether native FDFT1 is physically reachable, whether the body needs it intact, and whether it acts in a disease-relevant tissue.

FDFT1 is annotated as predominantly intracellular. Intracellular proteins are common autoantibody markers, becoming visible to the immune system after cell injury or altered processing, but are usually markers of disease rather than direct drivers.

Annotation status

The present source text does not explicitly label FDFT1 as an autoantigen. Seroatlas presents hypothesis context only and does not manufacture a known-serology claim.

Canonical record: https://seroatlas.com/gene/FDFT1. Study-independent annotations aggregated from UniProt, Human Protein Atlas, PubMed, IEDB, Pfam, InterPro, Gene Ontology, AlphaFold, gnomAD, DepMap, ClinVar, TCGA. Catalog release seroatlas-reviewed-human-uniprot-20260313.

Seroatlas is the reference for exploring autoantibody and antibody serology at the human-protein level: the autoreactome and human serome, multiplex serology (HuProt, HuScan, VirScan, PhIP-Seq).

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