ALOX12B
Arachidonate 12-Lipoxygenase, 12R Type
Gene Information Card
| Symbol | ALOX12B |
|---|---|
| Full Name | Arachidonate 12-Lipoxygenase, 12R Type |
| Gene Type | Protein coding |
| Chromosomal Location | 17p13.1 |
| NCBI Gene ID | 242 ncbi.nlm.nih.gov/gene/242 |
| Ensembl ID | ENSG00000179477 |
| UniProt ID | O75342 |
| OMIM ID | 603741 |
| HGNC ID | 430 |
| Aliases | 12R-LOX, 12(R)-lipoxygenase, ARCI2 |
Description
ALOX12B encodes a member of the lipoxygenase family that specifically catalyzes the conversion of arachidonic acid to 12(R)-hydroperoxyeicosatetraenoic acid. This enzyme is essential for the formation of the epidermal barrier, particularly in the synthesis of specialized lipids in the stratum corneum. Mutations in ALOX12B are a major cause of autosomal recessive congenital ichthyosis (ARCI), specifically non-bullous congenital ichthyosiform erythroderma (NCIE).
Disease Associations
| Disease category | Pathophysiological mechanism | Genomic evidence |
|---|---|---|
| Autosomal recessive congenital ichthyosis (ARCI) type 2 | Loss-of-function mutations impair 12R-lipoxygenase activity, disrupting epidermal lipid metabolism and barrier formation | OMIM #242100; multiple pathogenic variants reported in ClinVar |
| Non-bullous congenital ichthyosiform erythroderma (NCIE) | Deficient 12R-LOX leads to abnormal corneocyte lipid envelope and transepidermal water loss | ClinVar; HGMD |
Expression Profile
Tissue Expression
| Tissue | nTPM | level |
|---|---|---|
| Skin | 27.8 | High |
| Esophagus | 5.2 | Low |
| Lung | 1.1 | Not detected |
| Breast | 0.8 | Not detected |
Cell Line Expression
| Cell Line | nTPM | Notes |
|---|---|---|
| Keratinocytes (primary) | 45.0 | High expression; key for epidermal barrier |
| HaCaT (keratinocyte line) | 38.2 | Moderate-high expression |
| A431 (epidermoid carcinoma) | 12.5 | Moderate expression |
Data source：Human Protein Atlas（proteinatlas.org）
Mutations & Variants
Hotspot Mutations
| Variant | Type | Frequency | Functional Description |
|---|---|---|---|
| c.1561G>A (p.Gly521Arg) | Missense | Rare | Loss of enzymatic activity; associated with ARCI |
| c.1442C>T (p.Pro481Leu) | Missense | Rare | Reduced 12R-LOX function; reported in NCIE |
| c.1306C>T (p.Arg436*) | Nonsense | Rare | Premature truncation; complete loss of function |
Mutation functional classification
Loss of Function (LOF)
Most pathogenic mutations in ALOX12B result in loss of enzymatic activity, leading to defective epidermal barrier and ichthyosis.
Gain of Function (GOF)
No gain-of-function mutations have been reported for ALOX12B.
Dominant Negative (DN)
No dominant-negative effects have been described; inheritance is autosomal recessive.
View complete mutation data：
Gene Ontology (GO)
| • GO:0004052 – arachidonate 12-lipoxygenase activity | • GO:0005506 – iron ion binding |
| • GO:0019372 – lipoxygenase pathway | • GO:0030216 – keratinocyte differentiation |
| • GO:0006629 – lipid metabolic process | • GO:0005737 – cytoplasm |
Pathways
• Arachidonic acid metabolism (KEGG hsa00590)
• Epidermal barrier formation (Reactome R-HSA-6809371)
Protein Summary
ALOX12B encodes the 12R-lipoxygenase enzyme (701 amino acids, ~80 kDa), which contains a non-heme iron binding domain. It is predominantly expressed in the granular layer of the epidermis, where it oxygenates arachidonic acid to 12(R)-HPETE, a precursor for ceramide and acylceramide synthesis essential for skin barrier integrity. Loss of function leads to severe ichthyosis.
Related Services
Related Products
| Product name | Cat.No. | Species | Gene ID | |
|---|---|---|---|---|
| ALOX12B Knockout HEK293 Cell Line | EDC07792 | Human | 242 | Details Get a Quote |
| ALOX12B Knockout HCT 116 Cell Line | EDJ-KQ26396 | Human | 242 | Details Get a Quote |
| ALOX12B Knockout HeLa Cell Line | EDJ-KQ52598 | Human | 242 | Details Get a Quote |
| ALOX12B Knockout A-549 Cell Line | EDJ-KQ61075 | Human | 242 | Details Get a Quote |
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