OTC Deletion/Duplication Analysis

Clinical Use

Use

The OTC Deletion/Duplication Analysis is designed to identify pathogenic deletions and duplications in the OTC gene associated with ornithine transcarbamylase deficiency (OTC). OTC is an X-linked inherited disorder causing toxic ammonia accumulation, which can severely damage the nervous system. Clinical manifestations vary, with neonates experiencing acute symptoms leading to possible brain damage or liver failure. Symptoms in males typically include low muscle tone and feeding difficulties, while females may show variable symptoms. Early diagnosis and management are critical to prevent severe outcomes. Lifelong dietary management and sometimes liver transplantation are required, especially in the neonatal form of the disorder. Understanding the genetic basis of OTC is essential for effective treatment planning.

Special Instructions

This test code is only intended as a reflex test to UCD and Hyperammonemia Panel by Massively Parallel Sequencing (test code 2110).

Limitations

As with all genetic testing, a negative result does not completely rule out the presence of a pathogenic variant. Variants in other genes related to urea cycle disorders may not be detected. Furthermore, some deletions or duplications may fall below the assay's sensitivity threshold. Interpretation of results must be done cautiously, particularly in the context of a patient’s clinical history and family background. Results may vary due to biological factors affecting gene expression and penetrance of pathogenic variants.

Test Details