CGA (Glycoprotein Hormones, Alpha Polypeptide)
Alpha subunit of the glycoprotein hormone family, essential for TSH, FSH, LH, and hCG function.
Gene Information Card
| Symbol | CGA |
|---|---|
| Full Name | Glycoprotein Hormones, Alpha Polypeptide |
| Gene Type | protein-coding |
| Chromosomal Location | 6q14.3 |
| NCBI Gene ID | 1081 ncbi.nlm.nih.gov/gene/1081 |
| Ensembl ID | ENSG00000135363 |
| UniProt ID | P01215 |
| OMIM ID | 118850 |
| HGNC ID | 1885 |
| Aliases | FSHA, GPHa, HCG, LHA, TSHA, CG-alpha, chorionic gonadotropin alpha chain |
Description
The CGA gene encodes the alpha subunit of the glycoprotein hormones: chorionic gonadotropin (hCG), luteinizing hormone (LH), follicle-stimulating hormone (FSH), and thyroid-stimulating hormone (TSH). This alpha subunit is common to all four hormones and non-covalently associates with a hormone-specific beta subunit to form the biologically active heterodimer. The protein is synthesized in the anterior pituitary and placenta.
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Isolated hypogonadotropic hypogonadism | Mutations in CGA impair LH/FSH heterodimer formation, leading to deficient gonadotropin signaling | ClinVar, OMIM |
| Pituitary hormone deficiency, combined | Loss of functional TSH, FSH, LH due to defective alpha subunit | OMIM |
| Pregnancy loss / recurrent miscarriage | Altered hCG alpha subunit may affect implantation and early pregnancy maintenance | ClinVar |
| Thyroid dysgenesis (rare) | Defective TSH heterodimer leads to congenital hypothyroidism | OMIM |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Pituitary gland | 12.5 | Medium |
| Placenta | 8.3 | Medium |
| Testis | 1.2 | Low |
| Ovary | 0.9 | Low |
| Thyroid | 0.1 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| JEG-3 (choriocarcinoma) | 15.2 | High expression |
| BeWo (placental) | 10.1 | High expression |
| LNCaP (prostate) | 0.5 | Low expression |
| MCF7 (breast) | 0.2 | Not detected |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.74G>A (p.Arg25Gln) | Missense | <0.01% | Impaired heterodimer assembly; associated with hypogonadotropic hypogonadism |
| c.185G>A (p.Arg62His) | Missense | <0.01% | Reduced receptor binding; reported in combined pituitary hormone deficiency |
| c.320T>C (p.Leu107Pro) | Missense | <0.01% | Disrupts alpha-beta subunit interaction; loss of function |
Mutation functional classification
Loss of Function (LOF)
Missense mutations (e.g., p.Arg25Gln, p.Leu107Pro) disrupt subunit folding or heterodimerization, leading to loss of hormone activity.
Gain of Function (GOF)
Not reported for CGA.
Dominant Negative (DN)
Not reported; CGA mutations are typically recessive due to requirement for functional heterodimer.
View complete mutation data：
Gene Ontology (GO)
| • GO:0005179 – hormone activity | • GO:0005515 – protein binding |
| • GO:0005576 – extracellular region | • GO:0005615 – extracellular space |
| • GO:0031418 – L-ascorbic acid binding | • GO:0042802 – identical protein binding |
Pathways
• hsa04913 – Ovarian steroidogenesis
• hsa04914 – Progesterone-mediated oocyte maturation
• hsa04915 – Estrogen signaling pathway
• hsa04916 – Melanogenesis
• hsa04917 – Prolactin signaling pathway
• hsa04918 – Thyroid hormone synthesis
Protein Summary
The CGA protein (UniProt P01215) is a 116-amino acid glycoprotein hormone alpha chain. It contains 10 cysteine residues forming 5 disulfide bonds and two N-linked glycosylation sites (Asn52, Asn78). The mature protein is secreted and non-covalently associates with beta subunits of TSH, FSH, LH, and hCG. Glycosylation is essential for proper folding, secretion, and receptor activation.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| CGA、Beta-FSH Overexpression HEK293T Stable Cell Line | EDJ-GQ127 | Human | 1081 & 2488 | Details Get a Quote |
| CGA Knockout HEK293 Cell Line | EDJ-KQ1760 | Human | 1081 | Details Get a Quote |
| CGAS Knockout HEK293 Cell Line | EDJ-KQ3916 | Human | 115004 | Details Get a Quote |
| CGAS Knockout HeLa Cell Line | EDC90494 | Human | 115004 | Details Get a Quote |
| CGAS Knockout A-549 Cell Line | EDJ-KQ26140 | Human | 115004 | Details Get a Quote |
| CGA Knockout HeLa Cell Line | EDJ-KQ21637 | Human | 1081 | Details Get a Quote |
| Cgas Knockout 4T1 Cell Line | EDJ-KZ155 | Mouse | 214763 | Details Get a Quote |
| CGA Knockout A-549 Cell Line | EDJ-KQ61350 | Human | 1081 | Details Get a Quote |
| CGA Knockout HCT 116 Cell Line | EDJ-KQ69844 | Human | 1081 | Details Get a Quote |
| CGAS Knockout HCT 116 Cell Line | EDJ-KQ74860 | Human | 115004 | Details Get a Quote |
| CGAS Knockout THP-1 Cell Line | EDJ-KQ78073 | Human | 21367 | Details Get a Quote |
| Cgas Knock-in BV-2-cas9 Stable Cell Line | EDC06024 | Mouse | 115004 | Details Get a Quote |
Displaying Records 1 To 12 Of 12 Records
