Retinitis pigmentosa 36

Summary

Retinitis pigmentosa 36 (MONDO:0012523) is a disease caused by PRCD (GenCC Definitive), with 2 cohort genes.

At a glance

• Causal gene: PRCD (GenCC Definitive)
• Cohort genes: 2
• ClinVar variants: 10

Clinical features

No curated clinical features (Orphanet) for this disease.

Identifiers

Disease identifiers

Field	Value
Canonical name	retinitis pigmentosa 36
Mondo ID	MONDO:0012523
MeSH	C566431
OMIM	610599
DOID	DOID:0110405
UMLS	C1864621
MedGen	351175
GARD	0010403
Is cancer (heuristic)	no

Also known as: PRCD retinitis pigmentosa · retinitis pigmentosa 36 · retinitis pigmentosa caused by mutation in PRCD · retinitis pigmentosa type 36 · RP 36 · RP36

Data availability: 10 ClinVar variants · 4 GenCC gene-disease records.

Disease family

Classification path: disease › human disease › disease by body system or component › nervous system disorder › retinal disorder › retinal degeneration › inherited retinal dystrophy › retinitis pigmentosa › retinitis pigmentosa 36

Related subtypes (101): retinitis pigmentosa 6, cone-rod dystrophy 2, retinitis pigmentosa 1, retinitis pigmentosa 9, retinitis pigmentosa 10, dominant pericentral pigmentary retinopathy, late-adult onset retinitis pigmentosa, autosomal recessive pericentral pigmentary retinopathy, retinitis pigmentosa 3, retinitis pigmentosa 24, retinitis pigmentosa 23, retinitis pigmentosa 34, retinitis pigmentosa 2, retinitis pigmentosa Y-linked, retinitis pigmentosa 13, retinitis pigmentosa 12, retinitis pigmentosa 14, retinitis pigmentosa 11, retinitis pigmentosa 17, retinitis pigmentosa 18, retinitis pigmentosa 19, retinitis pigmentosa 22, retinitis pigmentosa 25, retinitis pigmentosa 28, retinitis pigmentosa 30, retinitis pigmentosa 7, retinitis pigmentosa 26, retinitis pigmentosa 32, retinitis pigmentosa 31, retinitis pigmentosa 35, retinitis pigmentosa 33, retinitis pigmentosa 37, retinitis pigmentosa 41, retinitis pigmentosa 29, retinitis pigmentosa 46, retinitis pigmentosa 42, retinitis pigmentosa 50, retinitis pigmentosa 54, retinitis pigmentosa 51, retinitis pigmentosa 55, retinitis pigmentosa 56, retinitis pigmentosa 57, retinitis pigmentosa 58, cone-rod dystrophy 15, retinitis pigmentosa 4, retinitis pigmentosa 27, retinitis pigmentosa 49, retinitis pigmentosa 47, retinitis pigmentosa 45, retinitis pigmentosa 44, retinitis pigmentosa 20, retinitis pigmentosa 40, retinitis pigmentosa 39, retinitis pigmentosa 43, retinitis pigmentosa 48, retinitis pigmentosa 59, retinitis pigmentosa 38, retinitis pigmentosa 60, retinitis pigmentosa 61, retinitis pigmentosa 62, retinitis pigmentosa 63, cone-rod dystrophy 16, retinitis pigmentosa 66, retinitis pigmentosa with or without situs inversus, retinitis pigmentosa 67, retinitis pigmentosa 68, retinitis pigmentosa 69, retinitis pigmentosa 70, retinal dystrophy and obesity, retinitis pigmentosa 71, retinitis pigmentosa 72, retinitis pigmentosa 73, retinitis pigmentosa 74, retinitis pigmentosa 75, retinitis pigmentosa 76, retinitis pigmentosa 77, retinitis pigmentosa 92, retinitis pigmentosa 93, retinitis pigmentosa 83, retinitis pigmentosa 84, retinitis pigmentosa 85, retinitis pigmentosa 86, retinitis pigmentosa 87 with choroidal involvement, retinitis pigmentosa 88, retinitis pigmentosa 90, retinitis pigmentosa 81, retinitis pigmentosa 78, retinitis pigmentosa 79, retinitis pigmentosa 80, retinitis pigmentosa 94, variable age at onset, retinitis pigmentosa 53, retinitis pigmentosa 65, retinitis pigmentosa 64, retinitis pigmentosa 95, retinitis pigmentosa 96, retinitis pigmentosa 97, retinitis pigmentosa 98, retinitis pigmentosa 99, retinitis pigmentosa 100, retinitis pigmentosa 101, retinitis pigmentosa 7, digenic

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

10 retrieved; paginated sample, class counts are floors:

4 pathogenic, 3 uncertain significance, 1 benign, 1 pathogenic/likely pathogenic, 1 likely pathogenic

ClinVar	Variant (HGVS)	Gene	Classification	Review
1184568	NM_001077620.3(PRCD):c.143+1G>A	CYGB	Pathogenic	no assertion criteria provided
866216	NM_001077620.3(PRCD):c.61_64del (p.Asn21fs)	CYGB	Pathogenic	criteria provided, multiple submitters, no conflicts
143095	NM_001077620.3(PRCD):c.2T>C (p.Met1Thr)	PRCD	Pathogenic/Likely pathogenic	criteria provided, multiple submitters, no conflicts
37041	NM_001077620.3(PRCD):c.64C>T (p.Arg22Ter)	PRCD	Pathogenic	criteria provided, multiple submitters, no conflicts
987020	NM_001077620.3(PRCD):c.52C>T (p.Arg18Ter)	PRCD	Pathogenic	criteria provided, multiple submitters, no conflicts
3583072	NM_001077620.3(PRCD):c.9del (p.Thr4fs)	CYGB	Likely pathogenic	criteria provided, single submitter
1188	NM_001077620.3(PRCD):c.5G>A (p.Cys2Tyr)	CYGB	Uncertain significance	criteria provided, multiple submitters, no conflicts
891110	NM_001077620.3(PRCD):c.13C>G (p.Leu5Val)	CYGB	Uncertain significance	criteria provided, multiple submitters, no conflicts
950646	NM_001077620.3(PRCD):c.85G>A (p.Asp29Asn)	CYGB	Uncertain significance	criteria provided, multiple submitters, no conflicts
1327441	NM_001077620.3(PRCD):c.74+36C>G	CYGB	Benign	criteria provided, multiple submitters, no conflicts

Genes & proteins

Mendelian disease overlap and somatic drivers

GenCC: 5 · Orphanet: 1 · 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
PRCD	Definitive	Autosomal recessive	retinitis pigmentosa 36	5

Orphanet rare-disease linkage (cohort genes)

Gene	Orphanet ID	Rare disease
PRCD	Orphanet:791	Retinitis pigmentosa

Cohort genes → proteins

2 cohort genes, 2 distinct canonical proteins.

Evidence partition

Subset	Genes
multi_evidence	2

Cohort genes (full)

Symbol	HGNC	Ensembl	UniProt	Name	Evidence
PRCD	HGNC:32528	ENSG00000214140	Q00LT1	Photoreceptor disk component PRCD	gencc,clinvar
CYGB	HGNC:16505	ENSG00000161544	Q8WWM9	Cytoglobin	clinvar

Cohort function summary

Lead sentence per gene, UniProt-curated.

Symbol	Protein name	Function (lead sentence)
PRCD	Photoreceptor disk component PRCD	Involved in vision.
CYGB	Cytoglobin	Probable multifunctional globin with a hexacoordinated heme iron required for the catalysis of various reactions depending on redox condition of the cell as well as oxygen availability.

Protein-family classification

Druggable: 0 · Difficult: 0 · Unknown: 2 · 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	2	1.8×	0.312

Per-gene assignment

Symbol	Family	Druggable?	EC	InterPro (top 3)
PRCD	Other/Unknown	no		PRCD
CYGB	Other/Unknown	no		Globin, Globin-like_sf, Globin/Proto

Expression context

Cohort genes with no expression data: 0.

2 cohort genes 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)	2
unknown	0

Top tissues across cohort

Tissue	Cohort genes
cerebellar cortex	1
cerebellar hemisphere	1
right hemisphere of cerebellum	1
cardiac muscle of right atrium	1
left ventricle myocardium	1
right atrium auricular region	1

Per-gene tissue summary (top 30)

Symbol	Bgee breadth	FANTOM5 breadth	SCXA	Top tissues
PRCD	196	broad	marker	right hemisphere of cerebellum, cerebellar hemisphere, cerebellar cortex
CYGB	219	ubiquitous	marker	cardiac muscle of right atrium, left ventricle myocardium, right atrium auricular region

Protein interactions among cohort

Intra-cohort edges: 0.

Hub genes (top 10 by interactor count)

Symbol	Interactor count
CYGB	1,338
PRCD	425

Structural data

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

Cohort genes with PDB structures (top 30)

Symbol	UniProt	PDB entries
CYGB	Q8WWM9	9

AlphaFold-only cohort genes (top 30 by pLDDT)

Symbol	UniProt	pLDDT
PRCD	Q00LT1	65.20

Function

Pathway analysis

Distinct Reactome pathways touched by cohort: 2. Enrichment computed across 2 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
Intracellular oxygen transport	1	2855.0×	7e-04	CYGB
eNOS activation	1	878.5×	0.001	CYGB

GO biological processes by enrichment

Over-representation of cohort genes vs the genome-wide background (hypergeometric test, Benjamini-Hochberg FDR; fold = observed/expected over 2 annotated cohort genes). Counts and members are kept as ground-truth; sorted by enrichment.

GO term	Cohort genes	Fold	FDR	Sample cohort genes
nitric oxide catabolic process	1	4213.0×	0.001	CYGB
negative regulation of hepatic stellate cell activation	1	4213.0×	0.001	CYGB
negative regulation of fibroblast migration	1	766.0×	0.003	CYGB
nitric oxide metabolic process	1	702.2×	0.003	CYGB
negative regulation of collagen biosynthetic process	1	561.7×	0.003	CYGB
oxygen transport	1	526.6×	0.003	CYGB
fatty acid oxidation	1	526.6×	0.003	CYGB
removal of superoxide radicals	1	526.6×	0.003	CYGB
detection of light stimulus involved in visual perception	1	324.1×	0.004	PRCD
response to oxidative stress	1	65.3×	0.017	CYGB
response to hypoxia	1	47.9×	0.021	CYGB

Therapeutics

Drug target analysis

Approved (phase 4): 0 · Phase ≥3: 0 · Phased (≥1): 0 · Undrugged: 2

Druggability breadth: 0 of 2 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
PRCD	0	0
CYGB	0	0

Bioactivity and enzyme data

Enzyme cohort genes (≥1 EC): 0.

Pharmacogenomics

Cohort genes with a PharmGKB record: 2; 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	2	PRCD, CYGB

Undrugged target profiles

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

Symbol	ChEMBL assays	Drugged partners (top 3)
PRCD	0	—
CYGB	0	—

Clinical trials & evidence

Clinical trials

Clinical trials: 0.