PCSK9

Chr 1AD

proprotein convertase subtilisin/kexin type 9

Also known as: FH3, FHCL3, HCHOLA3, LDLCQ1, NARC-1, NARC1, PC9

This gene encodes a member of the subtilisin-like proprotein convertase family, which includes proteases that process protein and peptide precursors trafficking through regulated or constitutive branches of the secretory pathway. The encoded protein undergoes an autocatalytic processing event with its prosegment in the ER and is constitutively secreted as an inactive protease into the extracellular matrix and trans-Golgi network. It is expressed in liver, intestine and kidney tissues and escorts specific receptors for lysosomal degradation. It plays a role in cholesterol and fatty acid metabolism. Mutations in this gene have been associated with autosomal dominant familial hypercholesterolemia. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Feb 2014]

GeneReviewsOMIMResearchGenerating clinical summary…
GOFmechanismADLOEUF 1.342 OMIM phenotypes
Clinical SummaryPCSK9
🧬
Gene-Disease Validity (ClinGen)
hypercholesterolemia, autosomal dominant, 3 · ADDefinitive

Definitive — sufficient evidence for diagnostic panels

Population Constraint (gnomAD)
Low constraint (pLI 0.00) — loss-of-function variants are relatively tolerated in the population.
📋
ClinVar Variants
20 unique Pathogenic / Likely Pathogenic· 761 VUS of 1542 total submissions
💊
Clinical Trials
12 active or recruiting trials — potential therapeutic options may be available
📖
GeneReview available — PCSK9
Authoritative clinical overview · Recommended first read
Open GeneReview ↗

Population Genetics & Constraint

gnomAD v4 — loss-of-function & missense intolerance

Tolerant — LoF & missense variants common in population
LoF Constraint?
1.34LOEUF
pLI 0.000
Z-score 0.16
OE 0.97 (0.711.34)
Tolerant

Highly tolerant — LoF variants common in population

Missense Constraint?
0.27Z-score
OE missense 0.96 (0.891.04)
419 obs / 435.0 exp
Tolerant

Mild missense constraint

Observed / Expected Ratios?
LoF OE?0.97 (0.711.34)
00.351.4
Missense OE?0.96 (0.891.04)
00.61.4
Synonymous OE?0.91
01.21.6
LoF obs/exp: 26 / 26.9Missense obs/exp: 419 / 435.0Syn Z: 1.01

This gene — mechanism propensity

DN
0.5870th %ile
GOF
0.5464th %ile
LOF
0.4234th %ile

The Badonyi & Marsh model scores dominant-negative highest, but genomic evidence most strongly supports gain-of-function as the primary mechanism.

GOF1 literature citation · 80% of P/LP are missense

Literature Evidence

GOFThe LDL-C and PCSK9 levels in patients with gain-of-function (GOF) variants of PCSK9 (n = 7) were mostly similar to those in patients with LDLR variants (n = 17) or variant-negative patients (n = 46).1

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

References

  1. 1.PMID 34652028

ClinVar Variant Classifications

1542 submitted variants in ClinVar

Classification Summary

Pathogenic10
Likely Pathogenic10
VUS761
Likely Benign556
Benign35
Conflicting165
10
Pathogenic
10
Likely Pathogenic
761
VUS
556
Likely Benign
35
Benign
165
Conflicting

Curated Variants Distribution

Classified variants from ClinVar · 5 ACMG categories

ClassificationLoFMissense + InframeNon-codingSynonymousTotal
Pathogenic
1
8
1
0
10
Likely Pathogenic
1
8
1
0
10
VUS
38
629
81
13
761
Likely Benign
49
31
145
331
556
Benign
0
2
32
1
35
Conflicting
165
Total896782603451,537

LoF = frameshift, stop gained/lost, canonical splice · Counts from ClinVar esearch · Updated hourly

View in ClinVar →

11 pathogenic / likely-pathogenic (of 15) ClinVar copy-number / structural variants overlap PCSK9 — these span large chromosomal regions, not the gene specifically, and are excluded from the counts above. Explore in CNV tools →

Protein Context — Lollipop Plot

PCSK9 · protein map & ClinVar variants

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

Clinical Trials

Active and recruiting trials from ClinicalTrials.gov

Familial Hypercholesterolemia

EAS Familial Hypercholesterolaemia Studies Collaboration

RECRUITING
NCT04272697Imperial College LondonStarted 2015-03-22
LDL Hyper-responsiveness

A Study of Genetic Influence on LDL Hyper-responsiveness in Patients Following a Ketogenic Diet

RECRUITING
NCT07137286Mayo ClinicStarted 2025-09-11
Familial Hypercholesterolemia

Clinical Exploration Trial of YOLT-101 in the Treatment of Familial Hypercholesterolemia (FH)

RECRUITING
NCT06458010Phase EARLY_PHASE1RenJi HospitalStarted 2024-05-24
YOLT-101
Elevated LDL-C and High Cholesterol

A Study of STX-1150 in Participants With Elevated Low-Density Lipoprotein Cholesterol (LDL-C)

RECRUITING
NCT07428473Phase PHASE1Monash UniversityStarted 2026-06
STX-1150
Hypercholesterolemia, FamilialHypercholesterolemia, Familial, 1Hypercholesterolemia, Familial, 2

Genetic Testing and Motivational Counseling for FH

ACTIVE NOT RECRUITING
NCT04656028Phase NANational Medical Research Center for Therapy and Preventive MedicineStarted 2020-06-15
Genetic TestingMotivational CounselingLipid analysis
Heterozygous Familial HypercholesterolemiaPremature Coronary Heart Disease

A Study of VERVE-102 in Patients With Familial Hypercholesterolemia or Premature Coronary Artery Disease

RECRUITING
NCT06164730Phase PHASE1Verve Therapeutics, Inc.Started 2024-04-30
VERVE-102
Familial Hypercholesterolemia

Russian Familial Hypercholesterolemia Registry

RECRUITING
NCT02208869Russian Cardiology Research and Production CenterStarted 2014-01
Ornithine Transcarbamylase DeficiencyOrnithine Transcarbamylase Deficiency DiseaseOrnithine Carbamoyltransferase Deficiency (Disorder)

An Open-label Study to Investigate ECUR-506 in Male Babies Less Than 9 Months of Age With Neonatal Onset OTC Deficiency

RECRUITING
NCT06255782Phase PHASE1, PHASE2iECURE, Inc.Started 2024-04-08
ECUR-506
Non-Small Cell Lung Cancer (NSCLC)HyperlipidemiaALK Gene Mutation

Management Strategy of 1L Lorlatinib With Hyperlipidemia in Stage IIIB-IV ALK Positive NSCLC

NOT YET RECRUITING
NCT07674524Sun Yat-sen UniversityStarted 2026-08-01
For Part A - Observational Cohort:Part B: Intensive Lipid-Lowering GroupFor Part B - Intensive Group
Type 1 Diabetes

Cholesterol Lowering and Residual Risk in Diabetes, Type 1

RECRUITING
NCT05641753Phase PHASE4NYU Langone HealthStarted 2022-12-06
Evolocumab CartridgeAtorvastatin Calcium TabletsEzetimibe Tablets
Familial Hypercholesterolemia

EPIRUS FH Reverse Cascade Screening

NOT YET RECRUITING
NCT05825612Hellenic Atherosclerosis SocietyStarted 2023-05
Type 2 DiabetesInflammationInsulin Sensitivity/Resistance

Targeting Risk Factors for Diabetes in Subjects With Normal Blood Cholesterol Using Omega-3 Fatty Acids

RECRUITING
NCT04485871Phase NAInstitut de Recherches Cliniques de MontrealStarted 2019-12-19
Omega-3 fatty acids