CTRB1
protein-codingchymotrypsinogen B1
Gene summary
This gene encodes a member of the serine protease family of enzymes and forms a principal precursor of the pancreatic proteolytic enzymes. The encoded preproprotein is synthesized in the acinar cells of the pancreas and secreted into the small intestine where it undergoes proteolytic activation to generate a functional enzyme. This CTRB1 gene is located head-to-head with the related CTRB2 gene. Some human populations have an alternate haplotype which inverts a 16.6 Kb region containing portions of intron 1, exon 1, and the upstream sequence of the CTRB1 and CTRB2 genes. In this inversion haplotype exon 1 and flanking sequence is swapped in CTRB1 and CTRB2. This inversion is associated with differential gene expression and increased risk for chronic pancreatitis. The GRCh38 assembly represents the minor allele for SNP rs8048956 of the CTRB1 gene. SNP rs8048956 in intron 1 of the CTRB2 gene is diagnostic for this inversion. This CTRB1 gene encodes distinct isoforms, some or all of which may undergo similar processing to generate the mature protein. [provided by RefSeq, Jan 2021]
- CTRB
MANE transcript
Inheritance
ClinVar variants
Top phenotype
gnomAD constraint
Max pathogenic AF
Genomic locus
External References & Databases
Transcript & Mutation Effects
hg38 • Region Span ~7.4 kbGenCC Phenotypes & Disease Associations
Curated gene-disease validity assertions and inheritance patterns
No GenCC data available for this gene.
ClinVar Associated Diseases & Phenotypes
Reported disease conditions connected to CTRB1 variants in ClinVar
ClinVar Variants & Pathogenicity by Type
Statistics based on transcript NM_001906.6. Only rare variants are included.
We include only reliable ClinVar variants with their consequences to MANE Select, MANE Plus Clinical transcripts, or transcripts with TSL equal to 1. Click a count to filter the variants table below.
Slight differences between displayed counts and ClinVar may occur due to a different transcript/consequence chosen by our variant effect predictor, or because we classify Benign/Likely benign as Likely benign and Pathogenic/Likely pathogenic as Likely pathogenic.
| Effect | PathogenicP | Likely pathogenicLP | VUS | Likely benignLB | BenignB | Sum |
|---|---|---|---|---|---|---|
| synonymous | 1 | 5 | 6 | |||
| missense | 56 | 6 | 62 | |||
| nonsense | 0 | |||||
| start loss | 0 | |||||
| frameshift | 0 | |||||
| splice donor/acceptor (+/-2bp) | 0 | |||||
| Total | 0 | 0 | 57 | 11 | 0 | 68 |
Transcript Catalog
Annotated transcript isoforms across RefSeq and Ensembl databases
| Transcript ID | Source | Protein ID | Coding Exons | MANE Status |
|---|---|---|---|---|
| RefSeq | NP_001897.4 | 7 | MANE Select | |
| Ensembl | ENSP00000354294.4 | 7 | MANE Select | |
| RefSeq | NP_001316119.1 | 6 | Standard | |
| Ensembl | ENSP00000463301.1 | 4 | Standard |
Gene Ontology (GO) Annotations & Pathways
Biological processes, molecular functions, cellular components and pathways
Pathways ConsensusPathDB
- Protein digestion and absorption - Homo sapiens (human)
- Pancreatic secretion - Homo sapiens (human)
- Extracellular matrix organization
- Activation of Matrix Metalloproteinases
- Degradation of the extracellular matrix
Biological Process
- proteolysis
- digestion
- cobalamin metabolic process
- extracellular matrix disassembly
Molecular Function
- serine-type endopeptidase activity
- serine-type peptidase activity
Cellular Component
- extracellular region
- extracellular space
gnomAD Constraint
Source:
- Gene type
- protein_coding
- Transcript type
- protein_coding
- Transcript
- ENST00000361017
- Coding exons
- 7
- Length
- 5925
- Individuals with no LoFs
- 125561
- Homozygous LoFs
- 0
- Heterozygous LoFs
- 14
- Defined
- 125575
- p
- 0.0000557
| Z-Score | Observed | Expected | Observed/Expected | Mutation Rate | Total Possible | |
|---|---|---|---|---|---|---|
| Missense | -0.531 | 131 | 115 | 1.14 | 0.00000677 | 1671 |
| Missense (PolyPhen) | 30 | 29.262 | 1.0252 | 477 | ||
| Synonymous | -0.844 | 61 | 53.2 | 1.15 | 0.00000386 | 531 |
| Loss of Function | -0.355 | 8 | 6.99 | 1.14 | 3.01e-7 | 116 |
Population LoF Frequency
| Population | CAF | p-value | Status |
|---|---|---|---|
| African | 0 | 0.0 | absent |
| Latino/Admixed American | 0.000065 | 0.000058 | rare |
| Ashkenazi Jewish | 0 | 0.0 | absent |
| East Asian | 0.000055 | 0.000054 | rare |
| Finnish | 0 | 0.0 | absent |
| European (Non-Finnish) | 0.000029 | 0.000026 | rare |
| South Asian | 0.00031 | 0.00026 | rare |
| Other | 0 | 0.0 | absent |
dbNSFP Gene Annotations
Source:
Recessive Scores
- pRec
- 0.152
Essentials
- Essential (CRISPR)
- N
- Essential (CRISPR2)
- N
- Essential (gene trap)
- N
- Indispensability pred.
- N
- Indispensability score
- 0.234
Gene Damage Prediction
| All | Recessive | Dominant | |
|---|---|---|---|
| Mendelian | Medium | Medium | Medium |
| Primary Immunodeficiency | Medium | Medium | Medium |
| Cancer | Medium | Medium | Medium |