On this page
PIEZO1
piezo type mechanosensitive ion channel component 1 (Er blood group)
PIEZO1 encodes a mechanosensitive ion channel protein critical for sensing physical forces and regulating cell volume, particularly in red blood cells. The PIEZO1 gene provides instructions for making a protein that forms an ion channel responsive to mechanical pressure.
PIEZO1 is located on the long (q) arm of chromosome 16, at band 16q24.3. Arm ratio per GRCh38 - banding schematic.
Explore chromosome 16 in the library →Overview
PIEZO1 encodes piezo type mechanosensitive ion channel component 1, a large transmembrane protein that detects and responds to mechanical forces such as cell stretch and fluid shear stress. The protein functions as an ion channel that opens in response to physical deformation, allowing calcium and other ions to flow across cell membranes. PIEZO1 is particularly important in red blood cells, where it helps regulate cell volume and maintain the characteristic biconcave shape necessary for efficient oxygen transport. The gene also plays roles in vascular development, bone formation, and lymphatic vessel function. Pathogenic variants in PIEZO1 can disrupt normal mechanosensory signalling, leading to inherited blood disorders and lymphatic abnormalities.
What the gene does
The PIEZO1 protein forms a mechanically activated ion channel that converts physical forces into electrical and chemical signals within cells. When the cell membrane experiences mechanical stress - such as stretching, compression, or shear flow - the PIEZO1 channel opens, permitting calcium and sodium ions to enter the cell. This ion influx triggers downstream signalling pathways that enable cells to respond appropriately to their physical environment.
In red blood cells, PIEZO1 channels sense changes in cell volume and membrane tension as the cells squeeze through narrow capillaries during circulation. The resulting calcium influx activates processes that regulate cell hydration and maintain the flexible, deformable shape essential for oxygen delivery. The channel also contributes to the normal turnover of ageing red blood cells by the spleen.
Beyond the bloodstream, PIEZO1 participates in vascular development by detecting blood flow patterns and helping to shape developing vessels. In the lymphatic system, the protein supports proper vessel formation and fluid balance. The mechanosensory capacity of PIEZO1 also influences bone remodelling, where cells must respond to physical loading and mechanical strain.
Video: Genetics 101
Chromosome location
PIEZO1 is located on the long arm of chromosome 16 at position 16q24.3. The gene spans a substantial genomic region and contains multiple exons that encode a protein of 2,521 amino acids. This chromosomal location is also designated the Er blood group locus, as PIEZO1 variants determine certain red blood cell antigens.
Protein structure
The PIEZO1 protein is an exceptionally large membrane-spanning structure composed of 2,521 amino acids. The protein contains several disordered regions, including segments spanning amino acids 738-769, 1356-1402, 1462-1498, 1576-1630, and 1811-1921, which provide flexibility to the channel architecture. A coiled coil domain is present at amino acids 1339-1368, likely contributing to protein-protein interactions or structural assembly. The overall architecture forms a three-bladed propeller-like structure that embeds in the cell membrane, with the mechanosensory apparatus responding to membrane curvature and tension to gate the central ion-conducting pore.
Key variants
Pathogenic variants in PIEZO1 generally result in gain-of-function effects, where the ion channel becomes more easily activated or remains open longer than normal. These alterations lead to excessive calcium influx and disrupted cellular ion balance. Most disease-causing variants follow an autosomal dominant inheritance pattern, meaning a single altered copy of the gene is sufficient to cause symptoms. Different variants can produce varying degrees of channel overactivity, contributing to the range of clinical severity observed in affected individuals.
Sample of pathogenic variants
10 pathogenic / likely-pathogenic variants from ClinVar, ranked by review status (expert-panel-reviewed first). This is a sample; recurrent founder variants in a specific population may not appear here - see the full ClinVar listing via the link above.
| Variant (HGVS) | Protein change | Classification | Evidence | Associated condition |
|---|---|---|---|---|
c.1264C>T | p.Gln422Ter | Pathogenic | ★★☆☆ | not provided |
c.1361G>A | p.Trp454Ter | Pathogenic/Likely pathogenic | ★★☆☆ | not provided |
c.1381C>T | p.Gln461Ter | Pathogenic/Likely pathogenic | ★★☆☆ | Dehydrated hereditary stomatocytosis with or without pseudohyperkalemia and/or perinatal edema |
c.1536_1537del | p.Cys513fs | Pathogenic/Likely pathogenic | ★★☆☆ | Thickened nuchal skin fold |
c.1792G>A | p.Val598Met | Pathogenic/Likely pathogenic | ★★☆☆ | Non-immune hydrops fetalis |
c.2005G>T | p.Asp669Tyr | Pathogenic/Likely pathogenic | ★★☆☆ | Dehydrated hereditary stomatocytosis with or without pseudohyperkalemia and/or perinatal edema |
c.3373C>T | p.Gln1125Ter | Pathogenic/Likely pathogenic | ★★☆☆ | Lymphatic malformation 6 |
c.3490C>T | p.Arg1164Ter | Pathogenic/Likely pathogenic | ★★☆☆ | Lymphatic malformation 6 |
c.4275_4278del | p.Ser1425fs | Pathogenic | ★★☆☆ | Inborn genetic diseases |
c.5289C>G | p.Tyr1763Ter | Pathogenic/Likely pathogenic | ★★☆☆ | Lymphatic malformation 6 |
Evidence stars indicate ClinVar review status. Individual variant interpretation should always be performed by a qualified clinical laboratory - many variants remain classified as Variants of Uncertain Significance (VUS) pending more research.
Associated conditions
Variants in PIEZO1 are primarily associated with dehydrated hereditary stomatocytosis, a condition characterised by red blood cells that lose excessive amounts of water and potassium, becoming dehydrated and less flexible. Affected individuals may experience anaemia, jaundice, and an enlarged spleen. Some PIEZO1 variants can also cause generalised lymphatic malformation when inherited in an autosomal recessive pattern, leading to abnormal development of lymphatic vessels and tissue swelling. The spectrum of PIEZO1-related conditions reflects the protein's diverse roles in red blood cell physiology and vascular development.
Inheritance pattern
Conditions caused by pathogenic PIEZO1 variants typically follow autosomal dominant inheritance.
Each child has a 50% chance of inheriting the pathogenic variant, regardless of sex.
UK clinical status
Within the NHS Genomic Medicine Service, PIEZO1 appears on multiple clinical gene panels with green (high evidence) classification. The gene is included in panels for cytopenias and congenital anaemias, rare anaemia (R92), foetal hydrops, foetal anomalies (R21), and primary lymphoedema (R136). It is also listed in the Developmental Disorders Genotype-to-Phenotype (DDG2P) database. This broad panel representation reflects the gene's importance in diagnosing inherited blood disorders and developmental abnormalities affecting the lymphatic and haematological systems.
Sources: NHS GMS PanelApp · Genomics England PanelApp · NHS National Genomic Test Directory
Frequently asked questions
What is dehydrated hereditary stomatocytosis?
Dehydrated hereditary stomatocytosis is an inherited blood disorder caused by PIEZO1 variants that lead to red blood cells losing excessive water and potassium. Affected cells become rigid and prone to early breakdown, resulting in anaemia, jaundice, and splenic enlargement.
How does PIEZO1 affect red blood cell shape?
PIEZO1 channels sense mechanical forces on the red blood cell membrane and regulate calcium influx, which controls cell volume and hydration. Proper channel function maintains the flexible biconcave shape necessary for cells to navigate small blood vessels efficiently.
Is PIEZO1 testing available through the NHS?
PIEZO1 genetic testing is available through the NHS Genomic Medicine Service for individuals meeting specific clinical criteria related to unexplained anaemia, hereditary blood disorders, lymphatic malformations, or foetal abnormalities. A healthcare provider can determine eligibility based on clinical presentation and family history.