Familial pseudohyperkalemia

Summary

Familial pseudohyperkalemia (MONDO:0012204) is a disease with 1 cohort gene.

At a glance

• Prevalence: Unknown (Worldwide) [Orphanet-validated]
• Cohort genes: 1
• ClinVar variants: 8
• Phenotypes (HPO): 6

Clinical features

Signs & symptoms

Clinical features (HPO)

6 HPO clinical features (Orphanet curated; top 6 by frequency):

HPO ID	Term	Frequency
HP:0002153	Hyperkalemia	Very frequent (80-99%)
HP:0000822	Hypertension	Frequent (30-79%)
HP:0004446	Stomatocytosis	Frequent (30-79%)
HP:0001923	Reticulocytosis	Occasional (5-29%)
HP:0005518	Increased mean corpuscular volume	Occasional (5-29%)
HP:0004802	Episodic hemolytic anemia	Very rare (<1-4%)

Identifiers

Disease identifiers

Field	Value
Canonical name	familial pseudohyperkalemia
Mondo ID	MONDO:0012204
MeSH	C563785
OMIM	609153
Orphanet	90044
ICD-11	1653996588
SNOMED CT	717254007
UMLS	C1836705
MedGen	324588
GARD	0016785
Is cancer (heuristic)	no

Also known as: pseudohyperkalemia, familial, 2, due to red cell leak · PSHK2

Data availability: 8 ClinVar variants · 2 GenCC gene-disease records.

Disease family

Classification path: disease › human disease › disease by body system or component › hematologic disorder › anemia › normocytic anemia › hemolytic anemia › familial hemolytic anemia › familial pseudohyperkalemia

Related subtypes (22): congenital nonspherocytic hemolytic anemia, elliptocytosis 2, southeast Asian ovalocytosis, overhydrated hereditary stomatocytosis, cryohydrocytosis, dehydrated hereditary stomatocytosis with or without pseudohyperkalemia and/or perinatal edema, abetalipoproteinemia, hemolytic anemia due to diphosphoglycerate mutase deficiency, glycogen storage disease VII, cutaneous porphyria, hereditary cryohydrocytosis with reduced stomatin, renal tubular acidosis, distal, 4, with hemolytic anemia, elliptocytosis 1, glycogen storage disease due to aldolase A deficiency, primary CD59 deficiency, triosephosphate isomerase deficiency, dehydrated hereditary stomatocytosis 2, Rh deficiency syndrome, hereditary spherocytosis, congenital dyserythropoietic anemia, X-linked congenital hemolytic anemia, hemolytic disease of fetus and newborn, RH-induced

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

8 retrieved; paginated sample, class counts are floors:

3 uncertain significance, 2 conflicting classifications of pathogenicity, 1 pathogenic, 1 likely pathogenic, 1 benign/likely benign

ClinVar	Variant (HGVS)	Gene	Classification	Review
218179	NM_005689.4(ABCB6):c.1124G>A (p.Arg375Gln)	ABCB6	Pathogenic	no assertion criteria provided
218180	NM_005689.4(ABCB6):c.1123C>T (p.Arg375Trp)	ABCB6	Likely pathogenic	criteria provided, single submitter
1283915	NM_005689.4(ABCB6):c.1511T>C (p.Val504Ala)	ABCB6	Conflicting classifications of pathogenicity	criteria provided, conflicting classifications
771341	NM_005689.4(ABCB6):c.1361T>C (p.Val454Ala)	ABCB6	Conflicting classifications of pathogenicity	criteria provided, conflicting classifications
218181	NM_005689.4(ABCB6):c.2168G>A (p.Arg723Gln)	ABCB6	Uncertain significance	criteria provided, multiple submitters, no conflicts
3585678	NM_005689.4(ABCB6):c.2359A>G (p.Thr787Ala)	ABCB6	Uncertain significance	criteria provided, single submitter
3585679	NM_005689.4(ABCB6):c.1864-4A>G	ABCB6	Uncertain significance	criteria provided, single submitter
783355	NM_005689.4(ABCB6):c.688-9C>T	ABCB6	Benign/Likely benign	criteria provided, multiple submitters, no conflicts

Genes & proteins

Mendelian disease overlap and somatic drivers

GenCC: 10 · Orphanet: 9 · 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
ABCB6	Supportive	Autosomal dominant	familial pseudohyperkalemia	10

Orphanet rare-disease linkage (cohort genes)

Gene	Orphanet ID	Rare disease
ABCB6	Orphanet:241	Dyschromatosis universalis hereditaria
ABCB6	Orphanet:90044	Familial pseudohyperkalemia
ABCB6	Orphanet:98938	Colobomatous microphthalmia
ABCB6	Orphanet:98942	Coloboma of choroid and retina
ABCB6	Orphanet:98943	Coloboma of eye lens
ABCB6	Orphanet:98944	Coloboma of iris
ABCB6	Orphanet:98945	Coloboma of macula
ABCB6	Orphanet:98946	Coloboma of eyelid
ABCB6	Orphanet:98947	Coloboma of optic disc

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
ABCB6	HGNC:47	ENSG00000115657	Q9NP58	ATP-binding cassette sub-family B member 6	gencc,clinvar

Cohort function summary

Lead sentence per gene, UniProt-curated.

Symbol	Protein name	Function (lead sentence)
ABCB6	ATP-binding cassette sub-family B member 6	ATP-dependent transporter that catalyzes the transport of a broad-spectrum of porphyrins from the cytoplasm to the extracellular space through the plasma membrane or into the vesicle lumen.

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
Transporter	1	77.8×	0.013

Per-gene assignment

Symbol	Family	Druggable?	EC	InterPro (top 3)
ABCB6	Transporter	yes		ABC_transporter-like_ATP-bd, AAA+_ATPase, ABC1_TM_dom

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
left ovary	1
right hemisphere of cerebellum	1
right ovary	1

Per-gene tissue summary (top 30)

Symbol	Bgee breadth	FANTOM5 breadth	SCXA	Top tissues
ABCB6	140	ubiquitous	marker	right ovary, right hemisphere of cerebellum, left ovary

Protein interactions among cohort

Intra-cohort edges: 0.

Hub genes (top 10 by interactor count)

Symbol	Interactor count
ABCB6	1,480

Structural data

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

Cohort genes with PDB structures (top 30)

Symbol	UniProt	PDB entries
ABCB6	Q9NP58	16

Function

Pathway analysis

Distinct Reactome pathways touched by cohort: 7. 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
Defective ABCB6 causes MCOPCB7	1	11420.0×	6e-04	ABCB6
Mitochondrial ABC transporters	1	2855.0×	0.001	ABCB6
ABC transporter disorders	1	439.2×	0.005	ABCB6
Disorders of transmembrane transporters	1	139.3×	0.012	ABCB6
ABC-family protein mediated transport	1	121.5×	0.012	ABCB6
Transport of small molecules	1	25.1×	0.046	ABCB6
Disease	1	13.1×	0.076	ABCB6

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
tetrapyrrole metabolic process	1	16852.0×	5e-04	ABCB6
heme transmembrane transport	1	8426.0×	5e-04	ABCB6
cellular detoxification of cadmium ion	1	5617.3×	5e-04	ABCB6
porphyrin-containing compound metabolic process	1	4213.0×	5e-04	ABCB6
porphyrin-containing compound biosynthetic process	1	4213.0×	5e-04	ABCB6
heme transport	1	4213.0×	5e-04	ABCB6
heme metabolic process	1	3370.4×	6e-04	ABCB6
intracellular copper ion homeostasis	1	936.2×	0.002	ABCB6
melanosome assembly	1	887.0×	0.002	ABCB6
skin development	1	443.5×	0.003	ABCB6
intracellular iron ion homeostasis	1	244.2×	0.005	ABCB6
transmembrane transport	1	168.5×	0.006	ABCB6
brain development	1	79.5×	0.013	ABCB6

Therapeutics

Drug target analysis

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

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

Top cohort targets by molecule count

Symbol	Molecules	Max phase
ABCB6	0	0

Bioactivity and enzyme data

Enzyme cohort genes (≥1 EC): 0.

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

Symbol	Assays	Type breakdown
ABCB6	3	Functional:3

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	1	ABCB6
D	Druggable family + AlphaFold only, no drug	0
E	Difficult family or no structure, no drug	0

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)
ABCB6	3	—

Clinical trials & evidence

Clinical trials

Clinical trials: 0.