GCNT2
Glucosaminyl (N-Acetyl) Transferase 2, I-Branching Enzyme
Gene Information Card
| Symbol | GCNT2 |
|---|---|
| Full Name | Glucosaminyl (N-Acetyl) Transferase 2, I-Branching Enzyme |
| Gene Type | Protein coding |
| Chromosomal Location | 6p24.3 |
| NCBI Gene ID | 2651 ncbi.nlm.nih.gov/gene/2651 |
| Ensembl ID | ENSG00000111846 |
| UniProt ID | Q8N0V4 |
| OMIM ID | 600429 |
| HGNC ID | 4199 |
| Aliases | GCNT2, I-branching enzyme, IGNT, NACGT2, GCNT5 |
Description
GCNT2 encodes the I-branching enzyme, a beta-1,6-N-acetylglucosaminyltransferase that converts the i antigen to the I antigen on erythrocytes and other tissues. This enzyme adds N-acetyllactosamine branches to polylactosamine chains, critical for blood group I determination. Mutations in GCNT2 cause congenital cataracts, often with blood group i phenotype.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Congenital cataracts, facial dysmorphism, and neuropathy (CCFDN) | Loss-of-function mutations in GCNT2 disrupt I-branching, leading to cataract formation and neurological defects. | ClinVar, OMIM |
| Blood group i phenotype | Homozygous or compound heterozygous GCNT2 mutations abolish I antigen expression, resulting in the rare i adult blood group. | OMIM, NCBI |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Whole blood | 12.3 | Medium |
| Spleen | 8.7 | Low |
| Bone marrow | 6.5 | Low |
| Liver | 4.2 | Low |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| K-562 | 15.1 | Erythroleukemia cell line |
| HEL | 11.8 | Erythroleukemia cell line |
| HL-60 | 9.3 | Promyeloblast cell line |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.114G>A (p.Trp38*) | Nonsense | Rare | Loss of function; associated with congenital cataracts and blood group i |
| c.947G>A (p.Arg316Gln) | Missense | Rare | Reduced enzyme activity; linked to blood group i phenotype |
Mutation functional classification
Loss of Function (LOF)
Nonsense and frameshift mutations cause complete loss of I-branching activity, leading to congenital cataracts and i blood group.
Gain of Function (GOF)
Not reported.
Dominant Negative (DN)
Not reported.
View complete mutation data：
Gene Ontology (GO)
| • N-acetyllactosaminide beta-1 | • 6-N-acetylglucosaminyltransferase activity |
| • Golgi membrane | • protein glycosylation |
| • blood group I antigen biosynthesis |
Pathways
• Blood group antigen biosynthesis
• Glycosphingolipid biosynthesis - lacto and neolacto series
Protein Summary
The GCNT2 protein is a type II transmembrane glycosyltransferase localized to the Golgi apparatus. It catalyzes the transfer of N-acetylglucosamine to the 6-position of galactose in polylactosamine chains, forming branched structures essential for the I blood group antigen. The enzyme is expressed in erythroid cells and various tissues, with isoforms generated by alternative splicing.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| GCNT2 Knockout HEK293 Cell Line | EDJ-KQ2638 | Human | 2651 | Details Get a Quote |
| GCNT2 Knockout A-549 Cell Line | EDJ-KQ23397 | Human | 2651 | Details Get a Quote |
| GCNT2 Knockout HeLa Cell Line | EDJ-KQ23398 | Human | 2651 | Details Get a Quote |
| GCNT2 Knockout HCT 116 Cell Line | EDJ-KQ70288 | Human | 2651 | Details Get a Quote |
Displaying Records 1 To 4 Of 4 Records
