CTRB1

chymotrypsinogen B1

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]

Known Variants35 total

rsidPosition (GRCh37)AllelesClassClinVar
rs805359516:75,252,103C/Tregulatory region variant—
rs75028354216:75,252,913C/T—likely benign
rs250730125716:75,252,924C/T—uncertain significance
rs77800915416:75,252,935C/G—uncertain significance
rs805516716:75,254,889T/Cintron variant—
rs804895616:75,254,966G/Cintron variant—
rs965266516:75,255,516T/G——
rs36920141316:75,256,686C/A—uncertain significance
rs37271636916:75,256,701G/A—uncertain significance
rs146027323716:75,256,711G/A—uncertain significance
rs57565010116:75,256,734G/A—uncertain significance
rs76072587716:75,256,735T/C—uncertain significance
rs53349485616:75,256,876G/A—uncertain significance
rs98892432916:75,256,908C/T—likely benign
rs139589568516:75,256,939G/A—uncertain significance
rs147587922016:75,257,055G/A—uncertain significance
rs250730915916:75,257,091A/G—likely benign
rs207670779416:75,257,113C/A—uncertain significance
rs74994776116:75,257,442G/A—uncertain significance
rs77853689916:75,257,463G/A—uncertain significance
rs132805856816:75,257,478G/T—uncertain significance
rs92297786916:75,257,986C/T—uncertain significance
rs74972939116:75,258,022C/T—likely benign
rs146830472516:75,258,034G/A—likely benign
rs137913218416:75,258,042G/A—uncertain significance
rs194168331816:75,258,046T/C—uncertain significance
rs77293980816:75,258,060G/A—uncertain significance
rs54943353016:75,258,101G/Aregulatory region variant—
rs19392078316:75,258,605C/T—uncertain significance
rs75502687816:75,258,609T/C—uncertain significance
rs37511229716:75,258,615G/A—uncertain significance
rs18707779616:75,258,678G/A—uncertain significance
rs56539497616:75,258,694C/T—uncertain significance
rs14624635716:75,258,714C/T—uncertain significance
rs166107014616:75,258,745A/C—uncertain significance

Gene information from NCBI Gene. Variant classifications from ClinVar.