Meyahealth
HomeGeneticsGeneTPI1 gene
Back to Gene
TPI1 gene
Reviewed by Medicinsk Expert•Last updated: 2026-10-22•Gene

TPI1 gene

The TPI1 gene provides instructions for making an enzyme essential for energy production, and mutations in this gene can lead to a rare condition called triosephosphate isomerase deficiency.

Normal Function

The TPI1 gene provides instructions for making an enzyme called triosephosphate isomerase 1. This enzyme is involved in a critical energy-producing process known as glycolysis, during which the simple sugar glucose is broken down to produce energy for cells. The enzyme carries out a specific reaction: the conversion of a molecule called dihydroxyacetone phosphate (DHAP) to glyceraldehyde 3-phosphate. This conversion is reversible, allowing the enzyme to also convert glyceraldehyde 3-phosphate back into DHAP. Additional steps in glycolysis eventually produce energy in the form of a molecule called ATP.

For the triosephosphate isomerase 1 enzyme to be active, it must bind to another molecule of the same enzyme, forming a two-enzyme complex called a dimer.

Triosephosphate isomerase deficiency

At least 12 mutations in the TPI1 gene have been found to cause triosephosphate isomerase deficiency. This condition is characterized by:

  • A shortage of red blood cells (anemia)
  • Movement problems
  • Increased susceptibility to infection
  • Muscle weakness affecting breathing and heart function

Mutations in this gene lead to the production of an enzyme with decreased activity, impairing glycolysis and reducing the cell's energy supply. Approximately 80 percent of cases are caused by a single mutation that replaces the amino acid glutamic acid with aspartic acid at position 104 (Glu104Asp or E104D). This mutation makes the enzyme unstable and impairs its ability to form a dimer.

Red blood cells are particularly affected because they rely solely on glucose breakdown for energy and lack alternative pathways to process DHAP. When the enzyme is non-functional, toxic levels of DHAP accumulate, causing red blood cells to die prematurely. Cells with high energy demands—such as nerve cells in the cerebellum, white blood cells, and cardiac muscle cells—are also susceptible to cell death due to the resulting energy deficit.

Other Names for This Gene

  • TIM
  • TPI
  • TPID
  • triose-phosphate isomerase
  • triosephosphate isomerase

Frequently Asked Questions

Early symptoms of triosephosphate isomerase deficiency can include chronic anemia (shortage of red blood cells), which may cause fatigue and paleness. As the condition progresses, children might develop movement problems, increased susceptibility to infections, and muscle weakness, potentially affecting breathing and heart function. Any combination of these persistent symptoms, particularly in infancy or early childhood, warrants prompt medical evaluation.
Currently, there is no cure for triosephosphate isomerase deficiency, and treatment focuses on managing symptoms. This may include blood transfusions for severe anemia, physical therapy for movement problems, and antibiotics to treat infections. In some cases, respiratory support may be needed. The long-term outlook varies depending on the severity of symptoms, but the condition can be life-limiting due to severe neurological and cardiac complications.
Yes, triosephosphate isomerase deficiency is an inherited genetic condition. It is typically passed down in an autosomal recessive pattern, meaning a child must inherit a mutated TPI1 gene from both parents to develop the disorder. If you have a family member with the condition, genetic counseling can help assess the risk for other family members and inform reproductive planning.
Diagnosis of triosephosphate isomerase deficiency typically involves a combination of blood tests to check for anemia and enzyme activity levels. A specific test measures the activity of the triosephosphate isomerase 1 enzyme in red blood cells. Genetic testing, usually performed on a blood sample, can confirm the diagnosis by identifying mutations in the TPI1 gene, such as the common Glu104Asp mutation.
Source: MedlinePlus, National Library of Medicine

MedlinePlus brings together authoritative health information from the National Library of Medicine (NLM), the National Institutes of Health (NIH), and other government agencies and health-related organizations.

Meyahealth

Ⓒ 2026. All rights reserved by MEYA

About UsTerms & PolicyFAQ