AGPS
protein-codingalkylglycerone phosphate synthase
Gene summary
This gene is a member of the FAD-binding oxidoreductase/transferase type 4 family. It encodes a protein that catalyzes the second step of ether lipid biosynthesis in which acyl-dihydroxyacetonephosphate (DHAP) is converted to alkyl-DHAP by the addition of a long chain alcohol and the removal of a long-chain acid anion. The protein is localized to the inner aspect of the peroxisomal membrane and requires FAD as a cofactor. Mutations in this gene have been associated with rhizomelic chondrodysplasia punctata, type 3 and Zellweger syndrome. [provided by RefSeq, Jul 2008]
MANE transcript
Inheritance
ClinVar variants
Top phenotype
gnomAD constraint
Max pathogenic AF
Genomic locus
External References & Databases
Transcript & Mutation Effects
hg38 • Region Span ~174.3 kbGenCC Phenotypes & Disease Associations
Curated gene-disease validity assertions and inheritance patterns
Inheritance Pattern: AR
Disease ID:MONDO:0010823
Submitter: PanelApp Australia
Inheritance Pattern: AR
Disease ID:MONDO:0010823
Submitter: Natera
Inheritance Pattern: AR
Disease ID:MONDO:0010823
Submitter: Labcorp Genetics (formerly Invitae)
Inheritance Pattern: AR
Disease ID:MONDO:0010823
Submitter: Ambry Genetics
Inheritance Pattern: AR
Disease ID:MONDO:0010823
Submitter: Laboratory for Molecular Medicine
This gene-disease relationship has undergone rapid assessment. Classifications are based on preliminary review of gene-disease validity during analysis of genomic sequencing results.
Inheritance Pattern: AR
Disease ID:MONDO:0100274
Submitter: ClinGen
The relationship between *AGPS* and alkylglycerone-phosphate synthase deficiency (rhizomelic chondrodysplasia punctata 3 [RCDP3] included), an autosomal recessive peroxisomal disorder, was evaluated using the ClinGen Clinical Validity Framework as of September 20, 2019 and updated by April 2022. *AGPS* encodes alkylglycerone-phosphate synthase (also known as alkyldihroxyacetonephosphate synthase, ADHAPS, alkyl-DHAP synthase), a peroxisomal enzyme catalyzing the second (last) step of plasmalogen synthesis. Deficiency of plasmalogens is a feature of RCDP. Variants in *AGPS* causing AGPS deficiency were first reported in 1998 (de Vet et al, PMID 9553082). Data from 8 patients with 9 unique variants (all missense except for one frameshift and one nonsense resulting from deletions) from six publications were curated (de Vet et al, 1998, PMID 9553082; de Vet et al, 1999, PMID 10553003; Thai et al, 2001, PMID 11152660; Itzkovitz et al, 2012, PMID 21990100; Noguchi et al, 2014, PMID 24849933, Shawi et al, 2021, PMID: 35070570). A total of 7.5 points were awarded for genetic evidence (note that this includes 2 points for a case for which the causative variant is unknown, and therefore the case could not be included in the summary matrix, but which appeared to be homozygous for a 128bp deletion in *AGPS* cDNA; PMID 10553003). The relationship between *AGPS* and AGPS deficiency is supported by experimental evidence including the biochemical function of AGPS which is consistent with the low levels of plasmalogens observed in individuals with AGPS deficiency (Brown et al, 1982, PMID 7096336; Nagan et al, 1997, PMID 9114014); the physical interaction of alkylglycerone-phosphate synthase with glyceronephosphate O-acyltransferase (encoded by GNPAT) which catalyzes the first step of plasmalogen synthesis (Biermann et al, 1999, PMID 102158610); the finding that the activity and level glyceronephosphate O-acyltransferase is dependent on the physical presence of alkylglycerone-phosphate synthase (de Vet et al, 1999, PMID 10553003; Itzkovitz et al, PMID 21990100); the knowledge that other genes with a role in plasmalogen synthesis (GNPAT, and PEX7 which encodes the PTS2 receptor necessary for important of AGPS into the peroxisomes) are implicated in causing RCDP (Hajra et al, 1995, PMID 8685243; Braverman et al, 1997, PMID 9090381; Braverman et al, 2012, PMID 20301447); the finding of reduced levels of *AGPS* cDNA and protein in patients with AGPS deficiency (Noguchi et al, 2014, PMID 24849933); and the features of a natural and two knock-out mouse models (Liegel et al, 2011, PMID 21353609; Liegel et al, 2014, PMID 25197626). More evidence may be available but the maximum points for experimental evidence (6 points) have been reached. In summary, *AGPS* is definitively associated with autosomal recessive AGPS deficiency. This has been repeatedly demonstrated in both the research and clinical diagnostic settings, and has been upheld over time.
Inheritance Pattern: AR
Disease ID:MONDO:0010823
Submitter: G2P
Clinical Genomic Database (CGD)
Manifestation: Biochemical; Musculoskeletal; Neurologic
Intervention: General
Rationale: Genetic knowledge may be beneficial related to issues such as selection of optimal supportive care, informed medical decision-making, prognostic considerations, and avoidance of unnecessary testing
ClinVar Associated Diseases & Phenotypes
Reported disease conditions connected to AGPS variants in ClinVar
ClinVar Variants & Pathogenicity by Type
Statistics based on transcript NM_003659.4. 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 | 8 | 267 | 4 | 279 | ||
| missense | 1 | 3 | 118 | 7 | 129 | |
| nonsense | 1 | 5 | 1 | 7 | ||
| start loss | 0 | |||||
| frameshift | 3 | 8 | 1 | 12 | ||
| splice donor/acceptor (+/-2bp) | 1 | 7 | 6 | 14 | ||
| Total | 6 | 23 | 134 | 274 | 4 | 441 |
Highest pathogenic variant AF is 0.000006583452
Transcript Catalog
Annotated transcript isoforms across RefSeq and Ensembl databases
| Transcript ID | Source | Protein ID | Coding Exons | MANE Status |
|---|---|---|---|---|
| RefSeq | NP_003650.1 | 20 | MANE Select | |
| Ensembl | ENSP00000264167.4 | 20 | MANE Select | |
| Ensembl | ENSP00000386688.1 | 5 | Standard | |
| Ensembl | ENSP00000386688.1 | 5 | Standard |
Gene Ontology (GO) Annotations & Pathways
Biological processes, molecular functions, cellular components and pathways
Pathways ConsensusPathDB
- Ether lipid metabolism - Homo sapiens (human)
- Peroxisome - Homo sapiens (human)
- Plasmalogen Synthesis
- Triacylglyceride Synthesis
- Metabolism of lipids
Biological Process
- protein targeting to peroxisome
- lipid biosynthetic process
- ether lipid biosynthetic process
- oxidation-reduction process
Molecular Function
- protein binding
- alkylglycerone-phosphate synthase activity
- oxidoreductase activity
- FAD binding
Cellular Component
- nucleolus
- mitochondrion
- peroxisome
- peroxisomal membrane
- peroxisomal matrix
gnomAD Constraint
Source:
- Gene type
- protein_coding
- Transcript type
- protein_coding
- Transcript
- ENST00000264167
- Coding exons
- 20
- Length
- 151193
- Individuals with no LoFs
- 125723
- Homozygous LoFs
- 0
- Heterozygous LoFs
- 5
- Defined
- 125728
- p
- 0.0000199
| Z-Score | Observed | Expected | Observed/Expected | Mutation Rate | Total Possible | |
|---|---|---|---|---|---|---|
| Missense | 3.23 | 186 | 358 | 0.520 | 0.0000172 | 4284 |
| Missense (PolyPhen) | 19 | 104.83 | 0.18125 | 1194 | ||
| Synonymous | 0.149 | 124 | 126 | 0.983 | 0.00000614 | 1245 |
| Loss of Function | 5.75 | 1 | 40.5 | 0.0247 | 0.00000200 | 487 |
Population LoF Frequency
| Population | CAF | p-value | Status |
|---|---|---|---|
| African | 0 | 0.0 | absent |
| Latino/Admixed American | 0 | 0.0 | absent |
| Ashkenazi Jewish | 0.000099 | 0.000099 | rare |
| East Asian | 0 | 0.0 | absent |
| Finnish | 0 | 0.0 | absent |
| European (Non-Finnish) | 0.000026 | 0.000026 | rare |
| South Asian | 0.000033 | 0.000033 | rare |
| Other | 0 | 0.0 | absent |
dbNSFP Gene Annotations
Source:
- Function
- FUNCTION: Catalyzes the exchange of an acyl for a long-chain alkyl group and the formation of the ether bond in the biosynthesis of ether phospholipids. {ECO:0000250}.;
- Disease
- DISEASE: Rhizomelic chondrodysplasia punctata 3 (RCDP3) [MIM:600121]: A form of rhizomelic chondrodysplasia punctata, a disease characterized by severely disturbed endochondral bone formation, rhizomelic shortening of femur and humerus, vertebral disorders, dwarfism, cataract, cutaneous lesions, facial dysmorphism, and severe mental retardation with spasticity. {ECO:0000269|PubMed:11152660, ECO:0000269|PubMed:21990100, ECO:0000269|PubMed:9553082}. Note=The disease is caused by mutations affecting the gene represented in this entry.;
Recessive Scores
- pRec
- 0.197
Intolerance Scores
- LoFtool
- 0.124
- RVIS EVS
- -0.38
- RVIS percentile EVS
- 27.42
Essentials
- Essential (CRISPR)
- E
- Essential (CRISPR2)
- N
- Essential (gene trap)
- N
- Indispensability pred.
- E
- Indispensability score
- 0.998
Gene Damage Prediction
| All | Recessive | Dominant | |
|---|---|---|---|
| Mendelian | Medium | Medium | Medium |
| Primary Immunodeficiency | Medium | Medium | Medium |
| Cancer | Medium | Medium | Medium |