Keratoderma hereditarium mutilans

Summary

Keratoderma hereditarium mutilans (MONDO:0007422) is a disease caused by GJB2 (GenCC Definitive), with 1 cohort gene.

At a glance

• Prevalence: <1 / 1 000 000 (Worldwide) [Orphanet-validated]
• Causal gene: GJB2 (GenCC Definitive)
• Cohort genes: 1
• ClinVar variants: 109
• Phenotypes (HPO): 17

Clinical features

Epidemiology

Prevalence records

2 prevalence record(s), Orphanet:

Type	Class	Value	Geography	Validation
Cases/families		50	Worldwide	Validated
Point prevalence	<1 / 1 000 000		Worldwide	Validated

Signs & symptoms

Clinical features (HPO)

17 HPO clinical features (Orphanet curated; top 17 by frequency):

HPO ID	Term	Frequency
HP:0000407	Sensorineural hearing impairment	Very frequent (80-99%)
HP:0000962	Hyperkeratosis	Very frequent (80-99%)
HP:0007460	Autoamputation of digits	Very frequent (80-99%)
HP:0007465	Honeycomb palmoplantar keratoderma	Very frequent (80-99%)
HP:0009775	Amniotic constriction ring	Very frequent (80-99%)
HP:0000044	Hypogonadotropic hypogonadism	Frequent (30-79%)
HP:0100543	Cognitive impairment	Frequent (30-79%)
HP:0000175	Cleft palate	Occasional (5-29%)
HP:0000365	Hearing impairment	Occasional (5-29%)
HP:0001596	Alopecia	Occasional (5-29%)
HP:0001597	Abnormality of the nail	Occasional (5-29%)
HP:0002143	Abnormality of the spinal cord	Occasional (5-29%)
HP:0002797	Osteolysis	Occasional (5-29%)
HP:0008064	Ichthyosis	Occasional (5-29%)
HP:0008388	Abnormal toenail morphology	Occasional (5-29%)
HP:0100716	Self-injurious behavior	Occasional (5-29%)
HP:0200034	Papule	Occasional (5-29%)

Identifiers

Disease identifiers

Field	Value
Canonical name	keratoderma hereditarium mutilans
Mondo ID	MONDO:0007422
MeSH	C536457
OMIM	124500
Orphanet	494
DOID	DOID:0111339
SNOMED CT	24559001
UMLS	C0265964
MedGen	78579
GARD	0003092
Is cancer (heuristic)	no

Also known as: keratoderma hereditarium mutilans · KHM · mutilating keratoderma of Vohwinkel · mutilating keratoderma plus deafness · PPK mutilans and deafness · Vohwinkel syndrome · VOWNKL

Data availability: 109 ClinVar variants · 3 GenCC gene-disease records.

Disease family

Classification path: disease › human disease › disease by body system or component › integumentary system disorder › keratoderma hereditarium mutilans

Related subtypes (35): Neu-Laxova syndrome, cutaneous mycosis, integumentary system benign neoplasm, integumentary system cancer, nipple neoplasm, nail disorder, disorder of pilosebaceous unit, Bartholin duct cyst, benign mammary dysplasia, skin disorder, breast fibrosis, breast mucosa-associated lymphoid tissue lymphoma, panniculitis, alopecia-epilepsy-pyorrhea-intellectual disability syndrome, autosomal dominant deafness - onychodystrophy syndrome, Rombo syndrome, Sjogren-Larsson syndrome, mucosulfatidosis, ichthyosis prematurity syndrome, ANE syndrome, frontonasal dysplasia with alopecia and genital anomaly, peeling skin-leukonuchia-acral punctate keratoses-cheilitis-knuckle pads syndrome, mandibulofacial dysostosis with alopecia, cutis laxa, X-linked ichthyosis syndrome, demodicidosis, Proteus-like syndrome, familial atypical multiple mole melanoma syndrome, familial tumoral calcinosis, subcutaneous tissue disorder, Bartholin gland neoplasm, pseudoxanthoma elasticum (inherited or acquired), skin appendage disorder, keratinization disease, paraneoplastic cutaneous syndrome

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

109 retrieved; paginated sample, class counts are floors:

36 pathogenic, 29 pathogenic/likely pathogenic, 15 uncertain significance, 11 likely pathogenic, 9 conflicting classifications of pathogenicity, 5 benign/likely benign, 2 likely benign, 2 benign

ClinVar	Variant (HGVS)	Gene	Classification	Review
158607	NM_004004.6(GJB2):c.298C>T (p.His100Tyr)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
158609	NM_004004.6(GJB2):c.647_650del (p.Arg216fs)	GJB2	Pathogenic/Likely pathogenic	criteria provided, multiple submitters, no conflicts
163514	NM_004004.6(GJB2):c.379C>T (p.Arg127Cys)	GJB2	Pathogenic/Likely pathogenic	criteria provided, multiple submitters, no conflicts
17000	NM_004004.6(GJB2):c.101T>C (p.Met34Thr)	GJB2	Pathogenic	reviewed by expert panel
17001	NM_004004.6(GJB2):c.231G>A (p.Trp77Ter)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
17002	NM_004004.6(GJB2):c.71G>A (p.Trp24Ter)	GJB2	Pathogenic	reviewed by expert panel
17003	NM_004004.6(GJB2):c.229T>C (p.Trp77Arg)	GJB2	Pathogenic/Likely pathogenic	criteria provided, multiple submitters, no conflicts
17004	NM_004004.6(GJB2):c.35del (p.Gly12fs)	GJB2	Pathogenic	reviewed by expert panel
17005	NM_004004.6(GJB2):c.139G>T (p.Glu47Ter)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
17006	NM_004004.6(GJB2):c.355GAG[1] (p.Glu120del)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
17007	NM_004004.6(GJB2):c.551G>C (p.Arg184Pro)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
17009	NM_004004.6(GJB2):c.427C>T (p.Arg143Trp)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
17010	NM_004004.6(GJB2):c.167del (p.Leu56fs)	GJB2	Pathogenic	reviewed by expert panel
17012	NM_004004.6(GJB2):c.196G>C (p.Asp66His)	GJB2	Pathogenic	no assertion criteria provided
17013	NM_004004.6(GJB2):c.51_62delinsA (p.Thr18fs)	GJB2	Pathogenic/Likely pathogenic	criteria provided, multiple submitters, no conflicts
17014	NM_004004.6(GJB2):c.235del (p.Leu79fs)	GJB2	Pathogenic	reviewed by expert panel
17016	NM_004004.6(GJB2):c.269T>C (p.Leu90Pro)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
17017	NM_004004.6(GJB2):c.428G>A (p.Arg143Gln)	GJB2	Pathogenic/Likely pathogenic	criteria provided, multiple submitters, no conflicts
17020	NM_004004.6(GJB2):c.148G>A (p.Asp50Asn)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
17023	NM_004004.6(GJB2):c.109G>A (p.Val37Ile)	GJB2	Pathogenic	reviewed by expert panel
17029	NM_004004.6(GJB2):c.-23+1G>A	GJB2	Pathogenic/Likely pathogenic	criteria provided, multiple submitters, no conflicts
17032	NM_004004.6(GJB2):c.250G>C (p.Val84Leu)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
17033	NM_004004.6(GJB2):c.134G>A (p.Gly45Glu)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
177737	NM_004004.6(GJB2):c.269dup (p.Val91fs)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
188756	NM_004004.6(GJB2):c.246C>G (p.Ile82Met)	GJB2	Pathogenic/Likely pathogenic	criteria provided, multiple submitters, no conflicts
188758	NM_004004.6(GJB2):c.94C>T (p.Arg32Cys)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
188821	NM_004004.6(GJB2):c.290dup (p.Tyr97Ter)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
188830	NM_004004.6(GJB2):c.131G>A (p.Trp44Ter)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
189051	NM_004004.6(GJB2):c.334_335del (p.Lys112fs)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts
189070	NM_004004.6(GJB2):c.508_511dup (p.Ala171fs)	GJB2	Pathogenic	criteria provided, multiple submitters, no conflicts

Genes & proteins

Mendelian disease overlap and somatic drivers

GenCC: 26 · 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
GJB2	Definitive	Autosomal dominant	keratoderma hereditarium mutilans	26

Orphanet rare-disease linkage (cohort genes)

Gene	Orphanet ID	Rare disease
GJB2	Orphanet:166286	Porokeratotic eccrine ostial and dermal duct nevus
GJB2	Orphanet:2202	Palmoplantar keratoderma-deafness syndrome
GJB2	Orphanet:2698	Knuckle pads-leukonychia-sensorineural deafness-palmoplantar hyperkeratosis syndrome
GJB2	Orphanet:477	KID syndrome
GJB2	Orphanet:494	Keratoderma hereditarium mutilans
GJB2	Orphanet:90635	Rare autosomal dominant non-syndromic sensorineural deafness type DFNA
GJB2	Orphanet:90636	Rare autosomal recessive non-syndromic sensorineural deafness type DFNB

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
GJB2	HGNC:4284	ENSG00000165474	P29033	Gap junction beta-2 protein	gencc,clinvar

Cohort function summary

Lead sentence per gene, UniProt-curated.

Symbol	Protein name	Function (lead sentence)
GJB2	Gap junction beta-2 protein	Structural component of gap junctions.

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)
GJB2	Other/Unknown	no		Connexin, Connexin26, Connexin_N

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
gingiva	1
gingival epithelium	1
penis	1

Per-gene tissue summary (top 30)

Symbol	Bgee breadth	FANTOM5 breadth	SCXA	Top tissues
GJB2	196	broad	marker	gingival epithelium, gingiva, penis

Protein interactions among cohort

Intra-cohort edges: 0.

Hub genes (top 10 by interactor count)

Symbol	Interactor count
GJB2	1,391

Structural data

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

Cohort genes with PDB structures (top 30)

Symbol	UniProt	PDB entries
GJB2	P29033	24

Function

Pathway analysis

Distinct Reactome pathways touched by cohort: 4. 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
Oligomerization of connexins into connexons	1	3806.7×	5e-04	GJB2
Transport of connexins along the secretory pathway	1	3806.7×	5e-04	GJB2
Transport of connexons to the plasma membrane	1	543.8×	0.002	GJB2
Gap junction assembly	1	292.8×	0.003	GJB2

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
gap junction-mediated intercellular transport	1	2808.7×	0.001	GJB2
gap junction assembly	1	2106.5×	0.001	GJB2
transmembrane transport	1	168.5×	0.010	GJB2
sensory perception of sound	1	100.9×	0.012	GJB2
cell-cell signaling	1	69.6×	0.014	GJB2

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
GJB2	KANAMYCIN

Top cohort targets by molecule count

Symbol	Molecules	Max phase
GJB2	1	4

Drugs targeting cohort genes (top 30)

Molecule	Max phase	Targets in cohort
KANAMYCIN	4	GJB2

Bioactivity and enzyme data

Enzyme cohort genes (≥1 EC): 0.

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

Symbol	Assays	Type breakdown
GJB2	5	Binding:5

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

1 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)
KANAMYCIN	4	GJB2

Druggability pyramid

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

Tier	Definition	Genes	Symbols
A	Approved (phase 4 drug)	1	GJB2
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.