PCDH8

Chr 13

protocadherin 8

Also known as: ARCADLIN, PAPC

PCDH8 encodes protocadherin-8, a calcium-dependent cell adhesion protein that functions in CNS-specific cell adhesion and may regulate synaptic reorganization and dendritic spine dynamics in hippocampal neurons. Mutations cause autosomal recessive intellectual disability with seizures and language delay. This gene is not highly constrained against loss-of-function variants.

OMIMResearchSummary from RefSeq, UniProt
MultiplemechanismLOEUF 0.81
Clinical SummaryPCDH8
Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint
0.81LOEUF
pLI 0.000
Z-score 2.26
OE 0.49 (0.300.81)
Tolerant

Typical tolerance to LoF variation

Missense Constraint
1.90Z-score
OE missense 0.77 (0.720.84)
439 obs / 566.5 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.49 (0.300.81)
00.351.4
Missense OE0.77 (0.720.84)
00.61.4
Synonymous OE0.95
01.21.6
LoF obs/exp: 11 / 22.6Missense obs/exp: 439 / 566.5Syn Z: 0.58
DN
0.77top 25%
GOF
0.80top 10%
LOF
0.3163th %ile

This gene has evidence for multiple mechanisms of pathogenicity (gain-of-function and dominant-negative). Both the Badonyi & Marsh prediction and the broader genomic evidence point to gain-of-function as the predominant mechanism. Different variants in this gene may act through different mechanisms — interpret in context of the specific variant.

GOFprediction above median
DNprediction above median

Note: In-silico variant effect predictors (SIFT, PolyPhen, REVEL, CADD) may underestimate pathogenicity of missense variants in genes with GOF or DN mechanisms. Consider functional evidence and clinical context.

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312.

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

PCDH8 · protein map & ClinVar variants

Showing all ClinVar variants across the protein. Search a specific variant to highlight its position.

3D Protein StructureAlphaFold

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

No active trials found for this gene.

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Clinical Literature
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