Transaldolase deficiency

A rare metabolic disorder affecting the pentose phosphate pathway

Transaldolase deficiency is a rare metabolic disorder that affects the pentose phosphate pathway, a crucial metabolic pathway in cells. This condition is caused by mutations in the TALDO1 gene, which encodes the enzyme transaldolase. Transaldolase plays a key role in the non-oxidative phase of the pentose phosphate pathway, facilitating the conversion of sugars for nucleotide and nucleic acid synthesis.

Presentation

Individuals with transaldolase deficiency may present with a variety of symptoms, including hepatosplenomegaly, liver dysfunction, and developmental delay. The condition can also lead to hemolytic anemia, thrombocytopenia, and renal tubular acidosis.

Pathophysiology

The pentose phosphate pathway is essential for the production of NADPH and ribose-5-phosphate. NADPH is crucial for biosynthetic reactions and antioxidant defense, while ribose-5-phosphate is a precursor for nucleotide synthesis. In transaldolase deficiency, the disruption of this pathway leads to an accumulation of intermediate metabolites, which can cause cellular damage and contribute to the clinical manifestations of the disorder.

Structure of transaldolase enzyme.

Genetics

Transaldolase deficiency is inherited in an autosomal recessive manner. Mutations in the TALDO1 gene reduce or eliminate the activity of the transaldolase enzyme, impairing the normal function of the pentose phosphate pathway.

Diagnosis

Diagnosis of transaldolase deficiency is based on clinical evaluation, biochemical testing, and genetic analysis. Elevated levels of certain metabolites in the urine, such as sedoheptulose-7-phosphate, can suggest the disorder. Genetic testing can confirm mutations in the TALDO1 gene.

Management

Currently, there is no specific treatment for transaldolase deficiency. Management focuses on supportive care and addressing individual symptoms. Regular monitoring of liver function and metabolic status is recommended.

Prognosis

The prognosis for individuals with transaldolase deficiency varies depending on the severity of the symptoms and the presence of complications. Early diagnosis and supportive care can improve outcomes.

Research

Ongoing research aims to better understand the molecular mechanisms of transaldolase deficiency and to develop potential therapeutic strategies.

Annotated pentose phosphate pathway showing the role of transaldolase.

Related pages

• Pentose phosphate pathway
• Metabolic disorder
• Enzyme deficiency

References

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  Transaldolase annotated PENTOSE PHOSPHATE Pathway