Sulfide quinone oxidoreductase deficiency

Summary

Sulfide quinone oxidoreductase deficiency (MONDO:0030982) is a disease caused by SQOR (GenCC Strong), with 1 cohort gene.

At a glance

• Causal gene: SQOR (GenCC Strong)
• Cohort genes: 1
• ClinVar variants: 3

Clinical features

No curated clinical features (Orphanet) for this disease.

Identifiers

Disease identifiers

Field	Value
Canonical name	sulfide quinone oxidoreductase deficiency
Mondo ID	MONDO:0030982
OMIM	619221
UMLS	C5543168
MedGen	1780603
GARD	0025671
Is cancer (heuristic)	no

Also known as: SQORD · sulfide:quinone oxidoreductase deficiency

Data availability: 3 ClinVar variants · 2 GenCC gene-disease records.

Disease family

Classification path: disease › human disease › disease by etiologic mechanism › disease of genetic or genomic mechanism › hereditary disease › inborn errors of metabolism › sulfide quinone oxidoreductase deficiency

Related subtypes (92): thiopurine metabolic disease, hypercalcemia, infantile, hypermanganesemia with dystonia, abdominal obesity-metabolic syndrome, plasma protein metabolism disease, inherited lipid metabolism disorder, lysosomal storage disease, striatonigral degeneration, inborn metal metabolism disorder, inborn vitamin metabolic disorder, chondrocalcinosis 2, Ehlers-Danlos syndrome, spondylodysplastic type, fish eye disease, aromatase excess syndrome, spondyloepiphyseal dysplasia with congenital joint dislocations, hypertriglyceridemia 1, autosomal dominant myoglobinuria, diastrophic dysplasia, hemolytic anemia due to diphosphoglycerate mutase deficiency, multiple epiphyseal dysplasia type 4, atelosteogenesis type II, inherited threoninemia, inborn glycerol kinase deficiency, achondrogenesis type IB, diabetes mellitus, noninsulin-dependent, 1, diabetes mellitus, noninsulin-dependent, 2, renal tubular acidosis, distal, 3, with or without sensorineural hearing loss, diabetes mellitus, noninsulin-dependent, 3, hypercholesterolemia, familial, 4, hypoalphalipoproteinemia, primary, 1, autosomal recessive proximal renal tubular acidosis, diabetes mellitus, noninsulin-dependent, 4, normophosphatemic familial tumoral calcinosis, apolipoprotein c-III deficiency, hypotonia-failure to thrive-microcephaly syndrome, chondrodysplasia with joint dislocations, gPAPP type, gluthathione peroxidase deficiency, congenital microcephaly - severe encephalopathy - progressive cerebral atrophy syndrome, diabetes mellitus, noninsulin-dependent, 5, congenital disorder of glycosylation, monogenic diabetes, 2-hydroxyglutaric aciduria, familial hypoparathyroidism, familial intrahepatic cholestasis, inborn aminoacylase deficiency, disorder of lysosomal-related organelles, inborn disorder of porphyrin metabolism, disorder of metabolite absorption and transport, autosomal dominant proximal renal tubular acidosis, neurodegeneration with brain iron accumulation, ferro-cerebro-cutaneous syndrome, familial hypocalciuric hypercalcemia, hypophosphatasia, hereditary amyloidosis, peroxisomal disease, inborn disorder of amino acid and other organic acid metabolism, inborn carbohydrate metabolic disorder, inborn disorder of energy metabolism, inborn disorder of biogenic amine metabolism and transport, inborn disorder of purine or pyrimidine metabolism, spondyloepimetaphyseal dysplasia, PAPSS2 type, hereditary lipodystrophy, hereditary recurrent myoglobinuria, DNA repair disease, 4-hydroxyphenylacetic aciduria, 5-nucleotidase syndrome, antigen-peptide-transporter 2 deficiency, APO A-i deficiency, cardiomyopathy hypogonadism metabolic anomalies, deficiency of coenzyme q cytochrome c reductase, defective apolipoprotein b-100, congenital disorder of deglycosylation, hypoalphalipoproteinemia, primary, 2, uridine-cytidineuria, NAD(P)HX dehydratase deficiency, inborn disorder of aspartate family metabolism, weinstein kliman scully syndrome, glycoprotein metabolism disease, inherited thyroid metabolism disease, tumoral calcinosis, hyperphosphatemic, familial, 2, tumoral calcinosis, hyperphosphatemic, familial, 3, combined ApoA-I and ApoC-III deficiency, familial hyperphosphatemic tumoral calcinosis/hyperphosphatemic hyperostosis syndrome, tumoral calcinosis, hyperphosphatemic, familial, 1, Waldenstrom macroglobulinemia, mucopolysaccharidosis or mucopolysaccharidosis-like disorder, disorder of peptide and amine metabolism, CFTR-related metabolic syndrome/CF screen positive, inconclusive diagnosis, Lane Hamilton syndrome, SQSTM1-related multisystem proteinopathy, hypertriglyceridemia 2, autosomal dominant dopa-responsive dystonia

Genetics & variants

GWAS landscape

No GWAS associations recorded — common-variant (GWAS) studies don’t cover this disease (typical for Mendelian / rare diseases). See the curated gene cohort and Mendelian overlap below.

Variant details and genetic-evidence tiers

ClinVar germline variants

3 retrieved; paginated sample, class counts are floors:

2 pathogenic, 1 uncertain significance

ClinVar	Variant (HGVS)	Gene	Classification	Review
1012234	NM_021199.4(SQOR):c.637G>A (p.Glu213Lys)	SQOR	Pathogenic	no assertion criteria provided
1012235	NM_021199.4(SQOR):c.446del (p.Leu149fs)	SQOR	Pathogenic	no assertion criteria provided
2507497	NM_021199.4(SQOR):c.182G>A (p.Arg61His)	SQOR	Uncertain significance	criteria provided, multiple submitters, no conflicts

Genes & proteins

Mendelian disease overlap and somatic drivers

GenCC: 2 · Orphanet: 0 · OMIM-shared: 0 · Dual-evidence (GWAS+Mendelian): 0

GenCC gene–disease validity (cohort genes)

the Disease column is the GenCC-asserted condition — a cohort gene’s strongest validity may be for a related predisposition syndrome.

Gene	Classification	Inheritance	Disease	Records
SQOR	Strong	Autosomal recessive	sulfide quinone oxidoreductase deficiency	2

Cohort genes → proteins

1 cohort genes, 1 distinct canonical proteins.

Evidence partition

Subset	Genes
multi_evidence	1

Cohort genes (full)

Symbol	HGNC	Ensembl	UniProt	Name	Evidence
SQOR	HGNC:20390	ENSG00000137767	Q9Y6N5	Sulfide:quinone oxidoreductase, mitochondrial	gencc,clinvar

Cohort function summary

Lead sentence per gene, UniProt-curated.

Symbol	Protein name	Function (lead sentence)
SQOR	Sulfide:quinone oxidoreductase, mitochondrial	Catalyzes the oxidation of hydrogen sulfide with the help of a quinone, such as ubiquinone-10, giving rise to thiosulfate and ultimately to sulfane (molecular sulfur) atoms.

Protein-family classification

Druggable: 1 · Difficult: 0 · Unknown: 0 · Druggable fraction: 1.0

Family distribution

Cohort families vs a genome-wide background (hypergeometric, BH-FDR; fold = observed/expected). Counts kept; sorted by enrichment, so the catch-all Other/Unknown bucket no longer leads.

Family	Genes	Fold	FDR
Enzyme (other)	1	12.0×	0.083

Per-gene assignment

Symbol	Family	Druggable?	EC	InterPro (top 3)
SQOR	Enzyme (other)	yes	1.8.5.4	Sulphide_quinone_reductase, FAD/NAD-binding_dom, FAD/NAD-bd_sf

Expression context

Cohort genes with no expression data: 0.

1 cohort gene are a single-cell marker in ≥1 SCXA experiment.

Breadth distribution (Bgee present_calls)

Bucket	Genes
narrow (1-5 tissues)	0
moderate (6-20)	0
broad (>20)	1
unknown	0

Top tissues across cohort

Tissue	Cohort genes
colonic mucosa	1
mucosa of sigmoid colon	1
mucosa of transverse colon	1

Per-gene tissue summary (top 30)

Symbol	Bgee breadth	FANTOM5 breadth	SCXA	Top tissues
SQOR	279	ubiquitous	marker	colonic mucosa, mucosa of sigmoid colon, mucosa of transverse colon

Protein interactions among cohort

Intra-cohort edges: 0.

Hub genes (top 10 by interactor count)

Symbol	Interactor count
SQOR	2,321

Structural data

PDB: 1 · AlphaFold-only: 0 · No structure: 0

Cohort genes with PDB structures (top 30)

Symbol	UniProt	PDB entries
SQOR	Q9Y6N5	8

Function

Pathway analysis

Distinct Reactome pathways touched by cohort: 5. Enrichment computed across 1 evidence-associated genes (1 with Reactome annotation).

Pathways by enrichment

Over-representation of cohort genes vs the genome-wide background (hypergeometric test, Benjamini-Hochberg FDR; fold = observed/expected over 1 annotated cohort genes). Counts and members are kept as ground-truth; sorted by enrichment.

Pathway	Cohort genes	Fold	FDR	Sample cohort genes
Sulfide oxidation to sulfate	1	1903.3×	0.003	SQOR
Degradation of cysteine and homocysteine	1	951.7×	0.003	SQOR
Sulfur amino acid metabolism	1	571.0×	0.003	SQOR
Metabolism of amino acids and derivatives	1	67.6×	0.018	SQOR
Metabolism	1	11.6×	0.086	SQOR

GO biological processes by enrichment

Over-representation of cohort genes vs the genome-wide background (hypergeometric test, Benjamini-Hochberg FDR; fold = observed/expected over 1 annotated cohort genes). Counts and members are kept as ground-truth; sorted by enrichment.

GO term	Cohort genes	Fold	FDR	Sample cohort genes
obsolete sulfide oxidation, using sulfide:quinone oxidoreductase	1	5617.3×	2e-04	SQOR

Therapeutics

Drug target analysis

Approved (phase 4): 1 · Phase ≥3: 1 · Phased (≥1): 1 · Undrugged: 0

Druggability breadth: 1 of 1 evidence-associated genes (100%) have a ChEMBL target (buckets above are over the deeply-mined display cohort).

Genes with an approved drug

The molecule shown is one approved compound that hits the gene — not necessarily a drug of choice or one indicated for this disease.

Symbol	Example approved molecule
SQOR	AUROTHIOGLUCOSE

Top cohort targets by molecule count

Symbol	Molecules	Max phase
SQOR	2	4

Drugs targeting cohort genes (top 30)

Molecule	Max phase	Targets in cohort
AUROTHIOGLUCOSE	4	SQOR
CARMOFUR	2	SQOR

Bioactivity and enzyme data

Enzyme cohort genes (≥1 EC): 1.

Cohort genes with ChEMBL bioactivity (full, sorted by assay count)

Symbol	Assays	Type breakdown
SQOR	4	Binding:4

Cohort enzymes (BRENDA EC)

Symbol	EC numbers	Names
SQOR	1.8.5.4, 1.8.5.8	bacterial sulfide:quinone reductase, eukaryotic sulfide quinone oxidoreductase

Pharmacogenomics

Cohort genes with a PharmGKB record: 1; with CPIC/DPWG dosing guidelines: 0.

No cohort gene has a CPIC/DPWG genotype-guided dosing guideline (PharmGKB).

Chemical tractability of cohort targets

2 approved/phased compounds have measured bioactivity against a cohort gene (and aren’t yet in disease-level trials). This is a research / tractability signal, NOT a therapeutic recommendation — a bioactivity row often reflects off-target or screening binding (e.g. promiscuous kinase inhibitors against a cohort kinase), implying no disease mechanism.

Compound	Max phase	Cohort target (bioactivity)
AUROTHIOGLUCOSE	4	SQOR
CARMOFUR	2	SQOR

Druggability pyramid

Cohort genes binned by druggability tier (high → low):

Tier	Definition	Genes	Symbols
A	Approved (phase 4 drug)	1	SQOR
B	Phased (≥1) drug, not yet approved	0
C	Druggable family + PDB, no drug	0
D	Druggable family + AlphaFold only, no drug	0
E	Difficult family or no structure, no drug	0

Undrugged target profiles

0 cohort genes are undrugged. Ranked by ‘starting-point quality’ (assay depth + drugged-partner adjacency).

Clinical trials & evidence

Clinical trials

Clinical trials: 0.