JPH1

Chr 8ADAR

junctophilin 1

Also known as: CMT2K, CMYO25, JP-1, JP1

Junctophilin-1 forms junctional membrane complexes that link the plasma membrane with the sarcoplasmic reticulum in skeletal muscle, providing structural foundation for calcium release during muscle contraction. Mutations cause autosomal recessive congenital myopathy with characteristic histopathologic features including abnormal triad structure and calcium handling defects. This gene is highly constrained against loss-of-function variants, indicating critical importance for normal muscle function.

OMIMResearchSummary from RefSeq, UniProt
LOFmechanismAD/ARLOEUF 0.412 OMIM phenotypes
Clinical SummaryJPH1
Population Constraint (gnomAD)
Moderately constrained gene (pLI 0.77) — some intolerance to loss-of-function variants.

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Moderate LoF intolerance
LoF Constraint
0.41LOEUF
pLI 0.767
Z-score 3.60
OE 0.18 (0.090.41)
Moderately constrained

More LoF-intolerant than ~75% of genes

Missense Constraint
1.46Z-score
OE missense 0.80 (0.730.88)
340 obs / 424.9 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios
LoF OE0.18 (0.090.41)
00.351.4
Missense OE0.80 (0.730.88)
00.61.4
Synonymous OE0.92
01.21.6
LoF obs/exp: 4 / 22.4Missense obs/exp: 340 / 424.9Syn Z: 0.87
Curated Mechanism (G2P)Gene2Phenotype (DDG2P) ↗
moderateJPH1-related congenital myopathy with ptosisLOFAR

Predictions shown for reference only — model trained on dominant genes, not applicable to AR conditions.

DN
0.4388th %ile
GOF
0.5465th %ile
LOF
0.71top 10%

The Badonyi & Marsh prediction model was trained exclusively on dominant disease genes. Predictions are not reliable for genes with autosomal recessive inheritance and are shown at reduced opacity for reference only.

Predictions from Badonyi M, Marsh JA. PLoS ONE. 2024;19(8):e0307312. Mechanism ranking also informed by gnomAD constraint, ClinVar, and ClinGen data.

ClinVar Variant Classifications

0 submitted variants in ClinVar

Protein Context — Lollipop Plot

JPH1 · 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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Full-Text Mentions
NLP-detected gene mentions in article bodies · via PubTator3
PubTator3
Top 5 full-text resultsSearch PubTator3 ↗
Recent Gene-Specific Literature
Gene in title · MEDLINE · newest first
Europe PMC

No open access results found