SORD Deficiency Disorder

Understanding SORD Deficiency Disorder

Another rare axonal subtype of Charcot-Marie-Tooth disease is SORD deficiency disorder, which affects the body’s ability to process a specific sugar molecule called sorbitol. This is caused by a mutation in the SORD gene, which provides instructions for making an enzyme called sorbitol dehydrogenase.

Sorbitol dehydrogenase helps to break down sorbitol into another molecule called fructose. Fructose can then be further processed by the body and used for energy. However, in individuals with SORD deficiency, the sorbitol dehydrogenase enzyme is either partially or completely non-functional, leading to a buildup of sorbitol in the body.

The excess sorbitol can cause a range of symptoms, including neurological problems, muscle weakness, and intellectual disability. Other common symptoms may include cataracts, liver damage, and an increased risk of developing diabetes. The severity of these symptoms can vary widely between individuals with SORD deficiency, and some people may not experience any symptoms at all.

SORD deficiency is inherited in an autosomal recessive pattern, which means that a person must inherit two copies of the mutated SORD gene (one from each parent) to develop the condition. SORD deficiency affects an estimated 1/100,000 individuals and is one of the most common causes of recessive hereditary neuropathy. There is currently no cure for SORD deficiency, and treatment options are generally focused on managing symptoms and improving quality of life.

How SORD Works

SORD (Sorbitol Dehydrogenase) deficiency leads to a specific subtype of Charcot-Marie-Tooth disease, distinguished by its unique metabolic pathway involvement. SORD works by converting sorbitol into fructose, a critical step in the sugar metabolism process.Mutations in the SORD gene disrupt this conversion, resulting in the buildup of sorbitol within cells. This accumulation becomes toxic to peripheral nerves and their neurons, ultimately causing impairment in both neuronal function and peripheral nerve health. This accumulation highlights the metabolic underpinnings of SORD-related neuropathy and underscores the importance of understanding genetic mutations in the diagnosis and management of Charcot-Marie-Tooth disease.

• Genetic Basis: Mutations in the SORD gene inhibit the normal conversion process from sorbitol to fructose.
• Metabolic Pathway Disruption: The accumulation of sorbitol within nerve cells contributes to the neuropathic symptoms observed in SORD deficiency.

SORD Symptoms

The symptoms of SORD deficiency mirror those of other types of Charcot-Marie-Tooth disease, with some unique distinctions due to its metabolic nature. Patients typically experience:

• Muscle Weakness and Atrophy: Primarily in the lower legs, leading to difficulties in walking and frequent tripping.
• Sensory Loss: Including a decreased ability to feel pain and temperature changes, particularly in the feet and hands.
• Foot Deformities: Such as high arches and hammer toes, resulting from uneven muscle pull on the foot.

Symptoms of SORD-CMT usually develop gradually and exhibit a wide range of severity across individuals, underscoring the complex nature of the disease. Research has shown a direct correlation between elevated sorbitol levels and increased overall symptom severity. Early diagnosis and management are crucial to mitigate the progression of these symptoms and improve the quality of life for affected individuals.

Treatment Options for SORD

Currently, there is no cure for SORD deficiency, but treatment focuses on managing symptoms and improving the patient’s quality of life. Treatment options include:

• Physical Therapy: To strengthen muscles, improve mobility, and prevent muscle stiffness.
• Orthopedic Devices: Such as braces or orthotic shoes, to support weak limbs and correct foot deformities.
• Pain Management: Through medications or therapies tailored to the individual’s symptoms and needs.

Researchers are also exploring gene therapy and other innovative treatments aimed at correcting the underlying genetic mutations in SORD deficiency. Participation in clinical trials and staying informed about the latest research developments can offer hope and potential new treatment avenues for individuals affected by this condition.

By integrating these sections, the page on SORD at the Charcot-Marie-Tooth Research Foundation website will offer comprehensive insights into how SORD works, its symptoms, and the current treatment landscape, providing valuable information to individuals and families affected by the condition.

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