MRCS syndrome

Summary

MRCS syndrome (MONDO:0016979) is a disease with 1 cohort gene.

At a glance

• Prevalence: <1 / 1 000 000 (Worldwide) [Orphanet-validated]
• Cohort genes: 1

Clinical features

Epidemiology

Prevalence records

2 prevalence record(s), Orphanet:

Type	Class	Value	Geography	Validation
Cases/families		7	Worldwide	Validated
Point prevalence	<1 / 1 000 000		Worldwide	Validated

Identifiers

Disease identifiers

Field	Value
Canonical name	MRCS syndrome
Mondo ID	MONDO:0016979
Orphanet	263347
ICD-11	392681472
UMLS	C4749856
MedGen	1666962
GARD	0017255
Is cancer (heuristic)	no

Also known as: microcornea-rod-cone dystrophy-cataract-posterior staphyloma syndrome

Data availability: 1 GenCC gene-disease record.

Disease family

Classification path: disease › human disease › disease by body system or component › nervous system disorder › retinal disorder › retinal degeneration › inherited retinal dystrophy › MRCS syndrome

Related subtypes (104): retinal dystrophies primarily involving Bruch’s membrane, vitreoretinal dystrophy, dystrophies primarily involving the retinal pigment epithelium, retinal dystrophy in systemic or cerebroretinal lipidoses, age-related macular degeneration, helicoid peripapillary chorioretinal degeneration, Sorsby fundus dystrophy, microcephaly with or without chorioretinopathy, lymphedema, or intellectual disability, pigmented paravenous retinochoroidal atrophy, retinoschisis, autosomal dominant, retinal vasculopathy with cerebral leukoencephalopathy and systemic manifestations, amaurosis-hypertrichosis syndrome, familial benign flecked retina, microcephaly and chorioretinopathy 1, ornithine aminotransferase deficiency, retinal degeneration-nanophthalmos-glaucoma syndrome, retinoschisis of fovea, Revesz syndrome, choroideremia, choroideremia-deafness-obesity syndrome, X-linked retinal dysplasia, X-linked retinoschisis, progressive bifocal chorioretinal atrophy, aceruloplasminemia, late-onset retinal degeneration, infantile cerebellar-retinal degeneration, progressive retinal dystrophy due to retinol transport defect, microcornea-myopic chorioretinal atrophy, retinal dystrophy with inner retinal dysfunction and ganglion cell anomalies, macular degeneration, early-onset, cone-rod dystrophy, ectopia lentis-chorioretinal dystrophy-myopia syndrome, foveal hypoplasia-presenile cataract syndrome, X-linked intellectual disability-limb spasticity-retinal dystrophy-diabetes insipidus syndrome, Leber congenital amaurosis, oligocone trichromacy, Oguchi disease, retinitis pigmentosa, hereditary macular dystrophy, RPE65-related recessive retinopathy, RPGR-related retinopathy, AIPL1-related retinopathy, RP2-related retinopathy, RDH5-related retinopathy, RLBP1-related retinopathy, LCA5-related retinopathy, ATF6-related retinopathy, RAB28-related retinopathy, FLVCR1-related retinopathy with or without ataxia, RPE65-related dominant retinopathy, GUCY2D retinopathy, PDE6A-related retinopathy, ELOVL4-related maculopathy, MAK-related retinopathy, KIZ-related retinopathy, TOPORS-related retinopathy, PRPF8-related retinopathy, RD3-related retinopathy, BEST1-related dominant retinopathy, BEST1-related recessive retinopathy, IMPG2-related recessive retinopathy, IMPG2-related dominant retinopathy, CACNA1F-related retinopathy, CACNA2D4-related retinopathy, CDHR1-related retinopathy, GUCA1A-related retinopathy, RHO-related retinopathy, SNRNP200-related dominant retinopathy, RDH12-related recessive retinopathy, RDH12-related dominant retinopathy, NMNAT1-related retinopathy, CNGA3-related retinopathy, EYS-related retinopathy, GNAT2-related retinopathy, IDH3B-related retinopathy, MERTK-related retinopathy, PRPF31-related retinopathy, GPR179-related retinopathy, GRM6-related retinopathy, ADAM9-related retinopathy, RP1-related recessive retinopathy, RP1-related dominant retinopathy, CERKL-related retinopathy, TRPM1-related retinopathy, CNGB1-related retinopathy, PCARE-related retinopathy, CNGA1-related retinopathy, ABCA4-related retinopathy, NYX-related retinopathy, retinal dystrophy, X-linked, Gardner-Hardcastle type, PDE6C-related retinopathy, PDE6G-related retinopathy, LRIT3-related retinopathy, IMPG1-related dominant retinopathy, IMPG1-related recessive retinopathy, TTLL5-related retinopathy, HGSNAT-related retinopathy, IMPDH1-related retinopathy, PRPH2-related retinopathy, PROM1-related retinopathy, KCNV2-related retinopathy, CRX-related retinopathy, REEP6-related retinopathy, SPATA7-related retinopathy

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

No tiered GWAS variants or ClinVar records for this disease.

Genes & proteins

Mendelian disease overlap and somatic drivers

GenCC: 22 · Orphanet: 7 · 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
BEST1	Supportive	Autosomal dominant	MRCS syndrome	22

Orphanet rare-disease linkage (cohort genes)

Gene	Orphanet ID	Rare disease
BEST1	Orphanet:1243	Best vitelliform macular dystrophy
BEST1	Orphanet:139455	Autosomal recessive bestrophinopathy
BEST1	Orphanet:263347	MRCS syndrome
BEST1	Orphanet:3086	Autosomal dominant vitreoretinochoroidopathy
BEST1	Orphanet:35612	Nanophthalmos
BEST1	Orphanet:791	Retinitis pigmentosa
BEST1	Orphanet:99000	Adult-onset foveomacular vitelliform dystrophy

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
BEST1	HGNC:12703	ENSG00000167995	O76090	Bestrophin-1	gencc

Cohort function summary

Lead sentence per gene, UniProt-curated.

Symbol	Protein name	Function (lead sentence)
BEST1	Bestrophin-1	Ligand-gated anion channel that allows the movement of anions across cell membranes when activated by calcium (Ca2+).

Protein-family classification

Druggable: 0 · Difficult: 0 · Unknown: 1 · Druggable fraction: 0.0

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
Other/Unknown	1	1.8×	0.558

Per-gene assignment

Symbol	Family	Druggable?	EC	InterPro (top 3)
BEST1	Other/Unknown	no		Bestrophin, Bestrophin-like

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
inferior olivary complex	1
lateral globus pallidus	1
pigmented layer of retina	1

Per-gene tissue summary (top 30)

Symbol	Bgee breadth	FANTOM5 breadth	SCXA	Top tissues
BEST1	209	ubiquitous	marker	pigmented layer of retina, lateral globus pallidus, inferior olivary complex

Protein interactions among cohort

Intra-cohort edges: 0.

Hub genes (top 10 by interactor count)

Symbol	Interactor count
BEST1	959

Structural data

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

Cohort genes with PDB structures (top 30)

Symbol	UniProt	PDB entries
BEST1	O76090	19

Function

Pathway analysis

Distinct Reactome pathways touched by cohort: 3. 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
Stimuli-sensing channels	1	135.9×	0.016	BEST1
Ion channel transport	1	96.0×	0.016	BEST1
Transport of small molecules	1	25.1×	0.040	BEST1

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
gamma-aminobutyric acid secretion, neurotransmission	1	8426.0×	0.001	BEST1
transepithelial chloride transport	1	1872.4×	0.002	BEST1
glutamate secretion	1	1685.2×	0.002	BEST1
regulation of calcium ion transport	1	802.5×	0.003	BEST1
protein complex oligomerization	1	674.1×	0.003	BEST1
detection of light stimulus involved in visual perception	1	648.1×	0.003	BEST1
chloride transport	1	455.5×	0.003	BEST1
regulation of synaptic plasticity	1	259.3×	0.005	BEST1
chloride transmembrane transport	1	237.3×	0.005	BEST1
monoatomic ion transmembrane transport	1	208.1×	0.005	BEST1
visual perception	1	79.5×	0.013	BEST1

Therapeutics

Drug target analysis

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

Druggability breadth: 0 of 1 evidence-associated genes (0%) have a ChEMBL target (buckets above are over the deeply-mined display cohort).

Top cohort targets by molecule count

Symbol	Molecules	Max phase
BEST1	0	0

Bioactivity and enzyme data

Enzyme cohort genes (≥1 EC): 0.

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

0 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.

Druggability pyramid

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

Tier	Definition	Genes	Symbols
A	Approved (phase 4 drug)	0
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	1	BEST1

Undrugged target profiles

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

Symbol	ChEMBL assays	Drugged partners (top 3)
BEST1	0	—

Clinical trials & evidence

Clinical trials

Clinical trials: 0.