PIP5K1C
protein-codingphosphatidylinositol-4-phosphate 5-kinase type 1 gamma
Gene summary
This locus encodes a type I phosphatidylinositol 4-phosphate 5-kinase. The encoded protein catalyzes phosphorylation of phosphatidylinositol 4-phosphate, producing phosphatidylinositol 4,5-bisphosphate. This enzyme is found at synapses and has been found to play roles in endocytosis and cell migration. Mutations at this locus have been associated with lethal congenital contractural syndrome. Alternatively spliced transcript variants encoding different isoforms have been described.[provided by RefSeq, Sep 2010]
MANE transcript
Inheritance
ClinVar variants
Top phenotype
gnomAD constraint
Max pathogenic AF
Genomic locus
External References & Databases
Transcript & Mutation Effects
hg38 • Region Span ~70.3 kbGenCC Phenotypes & Disease Associations
Curated gene-disease validity assertions and inheritance patterns
Inheritance Pattern: AR
Disease ID:MONDO:0012656
Submitter: G2P
Inheritance Pattern: AD
Disease ID:MONDO:0100038
Submitter: Ambry Genetics
Inheritance Pattern: AR
Disease ID:MONDO:0012656
Submitter: PanelApp Australia
Inheritance Pattern: AD
Disease ID:MONDO:0100038
Submitter: PanelApp Australia
Inheritance Pattern: AD
Disease ID:MONDO:1010145
Submitter: ClinGen
*PIP5K1C* encodes phosphatidylinositol phosphate kinase type 1 gamma (PIP5KIγ), which phosphorylates phosphatidylinositol 4-phosphate (PI4P) to produce phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2), a membrane lipid that plays essential roles in multiple cellular processes in the brain. *PIP5K1C* was first reported in relation to autosomal dominant PIP5K1C-related neurodevelopmental disorder in 2023 (Morleo et al., PMID: 37451268). Affected individuals present with developmental delay, intellectual disability, acquired microcephaly, seizures, visual abnormalities, dysmorphic features, and brain MRI abnormalities. Three *de novo* missense variants that have been reported in 9 probands in one publication (PMID: 37451268) are included in this curation. One variant, p.Tyr221Cys, was identified in 6 unrelated individuals. The three reported variants are located in the catalytic domain of the PIP5KIγ protein kinase. Additional *de novo* missense variants have been reported in individuals with developmental disorders (PMID: 33057194), but they were not included in this curation because there is no functional evidence supporting their pathogenicity. The mechanism of pathogenicity is reported to be gain of function, resulting in increased PI(4,5)P2 levels. Consistent with this mechanism, increased PI(4,5)P2 levels due to pathogenic mutations in phosphatases that dephosphorylate PI(4,5)P2 have been implicated in neurodevelopmental disorders, including Lowe (*OCRL*) and Joubert (*INPP5E*) syndromes and congenital muscular dystrophy with cataracts and intellectual disability (*INPP5K*) (PMID: 37451268). This gene-disease relationship is also supported by experimental evidence, including functional alteration in patient cells, shared biochemical function with established disease genes, and zebrafish models expressing patient variants that recapitulate aspects of the human phenotype (PMID: 37451268). Of note, biallelic variants in *PIP5K1C* leading to loss of function have been reported in relation to autosomal recessive lethal congenital contractural syndrome 3 (PMIDs: 17701898, 38491417). This assertion will be assessed separately. In summary, there is definitive evidence supporting the relationship between *PIP5K1C* and autosomal dominant PIP5K1C-related neurodevelopmental disorder. This has been repeatedly demonstrated in both the research and clinical diagnostic settings, and has been upheld over time. This gene-disease pair was originally evaluated by the ClinGen Intellectual Disability and Autism Gene Curation Expert Panel on May 7, 2025. It was reevaluated on October 14, 2026 (SOP Version 12). As a result of this reevaluation, no new cases were found but the classification increased from Strong to Definitive because no contradictory evidence has emerged in the three years since the first publication.
Inheritance Pattern: AD
Disease ID:MONDO:0700092
Submitter: G2P
Inheritance Pattern: AR
Disease ID:MONDO:0012656
Submitter: Labcorp Genetics (formerly Invitae)
Inheritance Pattern: AR
Disease ID:MONDO:0012656
Submitter: Orphanet
Clinical Genomic Database (CGD)
Manifestation: Musculoskeletal
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 PIP5K1C variants in ClinVar
ClinVar Variants & Pathogenicity by Type
Statistics based on transcript NM_012398.3. 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 | 42 | 3 | 45 | |||
| missense | 4 | 3 | 131 | 10 | 1 | 149 |
| nonsense | 1 | 1 | ||||
| start loss | 0 | |||||
| frameshift | 1 | 1 | 4 | 6 | ||
| splice donor/acceptor (+/-2bp) | 1 | 2 | 3 | |||
| Total | 6 | 4 | 138 | 52 | 4 | 204 |
Highest pathogenic variant AF is 0.000017970164
Transcript Catalog
Annotated transcript isoforms across RefSeq and Ensembl databases
| Transcript ID | Source | Protein ID | Coding Exons | MANE Status |
|---|---|---|---|---|
| RefSeq | NP_036530.1 | 18 | MANE Select | |
| Ensembl | ENSP00000335333.3 | 18 | MANE Select | |
| RefSeq | NP_001182662.1 | 17 | Standard | |
| RefSeq | NP_001287778.1 | 17 | Standard |
Gene Ontology (GO) Annotations & Pathways
Biological processes, molecular functions, cellular components and pathways
Pathways ConsensusPathDB
- Focal adhesion - Homo sapiens (human)
- Fc gamma R-mediated phagocytosis - Homo sapiens (human)
- Inositol phosphate metabolism - Homo sapiens (human)
- Choline metabolism in cancer - Homo sapiens (human)
- Endocytosis - Homo sapiens (human)
Biological Process
- phosphatidylinositol biosynthetic process
- phagocytosis
- regulation of phosphatidylinositol 3-kinase signaling
- synaptic vesicle exocytosis
- actin cytoskeleton organization
Molecular Function
- protein binding
- ATP binding
- 1-phosphatidylinositol-4-phosphate 5-kinase activity
- 1-phosphatidylinositol-3-phosphate 4-kinase activity
- phosphatidylinositol-3,4-bisphosphate 5-kinase activity
Cellular Component
- phagocytic cup
- uropod
- nucleoplasm
- cytosol
- focal adhesion
gnomAD Constraint
Source:
- Gene type
- protein_coding
- Transcript type
- protein_coding
- Transcript
- ENST00000335312
- Coding exons
- 17
- Length
- 70297
- Individuals with no LoFs
- 125726
- Homozygous LoFs
- 0
- Heterozygous LoFs
- 16
- Defined
- 125742
- p
- 0.0000636
| Z-Score | Observed | Expected | Observed/Expected | Mutation Rate | Total Possible | |
|---|---|---|---|---|---|---|
| Missense | 2.29 | 300 | 434 | 0.690 | 0.0000328 | 4315 |
| Missense (PolyPhen) | 97 | 195.55 | 0.49603 | 1867 | ||
| Synonymous | -3.60 | 267 | 202 | 1.32 | 0.0000175 | 1327 |
| Loss of Function | 4.57 | 5 | 33.6 | 0.149 | 0.00000164 | 402 |
Population LoF Frequency
| Population | CAF | p-value | Status |
|---|---|---|---|
| African | 0.00013 | 0.00012 | rare |
| Latino/Admixed American | 0.000029 | 0.000029 | rare |
| Ashkenazi Jewish | 0 | 0.0 | absent |
| East Asian | 0.00016 | 0.00016 | rare |
| Finnish | 0 | 0.0 | absent |
| European (Non-Finnish) | 0.000081 | 0.000079 | rare |
| South Asian | 0.000033 | 0.000033 | rare |
| Other | 0 | 0.0 | absent |
dbNSFP Gene Annotations
Source:
- Function
- FUNCTION: Catalyzes the phosphorylation of phosphatidylinositol 4- phosphate (PtdIns4P) to form phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P2). PtdIns(4,5)P2 is involved in a variety of cellular processes and is the substrate to form phosphatidylinositol 3,4,5-trisphosphate (PtdIns(3,4,5)P3), another second messenger. The majority of PtdIns(4,5)P2 is thought to occur via type I phosphatidylinositol 4-phosphate 5-kinases given the abundance of PtdIns4P. Participates in a variety of cellular processes such as vesicle mediated transport, cell adhesion, cell polarization and cell migration. Together with PIP5K1A is required for phagocytosis, but they regulate different types of actin remodeling at sequential steps. Promotes particle attachment by generating the pool of PtdIns(4,5)P2 that induces controlled actin depolymerization to facilitate Fc-gamma-R clustering. Mediates RAC1-dependent reorganization of actin filaments. Required for synaptic vesicle transport. Controls the plasma membrane pool of PtdIns(4,5)P2 implicated in synaptic vesicle endocytosis and exocytosis. Plays a role in endocytosis mediated by clathrin and AP-2 (adaptor protein complex 2). Required for clathrin-coated pits assembly at the synapse. Participates in cell junction assembly. Modulates adherens junctions formation by facilitating CDH1 trafficking. Required for focal adhesion dynamics. Modulates the targeting of talins (TLN1 and TLN2) to the plasma membrane and their efficient assembly into focal adhesions. Regulates the interaction between talins (TLN1 and TLN2) and beta-integrins. Required for uropodium formation and retraction of the cell rear during directed migration. Has a role in growth factor- stimulated directional cell migration and adhesion. Required for talin assembly into nascent adhesions forming at the leading edge toward the direction of the growth factor. Negative regulator of T-cell activation and adhesion. Negatively regulates integrin alpha-L/beta-2 (LFA-1) polarization and adhesion induced by T-cell receptor. Together with PIP5K1A has a role during embryogenesis and together with PIP5K1B may have a role immediately after birth. {ECO:0000269|PubMed:12422219, ECO:0000269|PubMed:12847086, ECO:0000269|PubMed:17261850, ECO:0000269|PubMed:17635937}.;
- Disease
- DISEASE: Lethal congenital contracture syndrome 3 (LCCS3) [MIM:611369]: A form of lethal congenital contracture syndrome, an autosomal recessive disorder characterized by degeneration of anterior horn neurons, extreme skeletal muscle atrophy, and congenital non-progressive joint contractures (arthrogryposis). The contractures can involve the upper or lower limbs and/or the vertebral column, leading to various degrees of flexion or extension limitations evident at birth. LCCS3 patients present at birth with severe multiple joint contractures and severe muscle wasting and atrophy, mainly in the legs. Death occurs minutes to hours after birth due to respiratory insufficiency. The phenotype can be distinguished from that of LCCS1 by the absence of hydrops, fractures and multiple pterygia, and from LCCS2 by the absence of neurogenic bladder defect. {ECO:0000269|PubMed:17701898}. Note=The disease is caused by mutations affecting the gene represented in this entry.;
Recessive Scores
- pRec
- 0.167
Intolerance Scores
- LoFtool
- 0.269
- RVIS EVS
- -0.31
- RVIS percentile EVS
- 32.23
Essentials
- Essential (CRISPR)
- N
- Essential (CRISPR2)
- N
- Essential (gene trap)
- N
- Indispensability pred.
- E
- Indispensability score
- 0.981
Gene Damage Prediction
| All | Recessive | Dominant | |
|---|---|---|---|
| Mendelian | Medium | Medium | Medium |
| Primary Immunodeficiency | Medium | Medium | Medium |
| Cancer | Medium | Medium | Medium |