peroxisome biogenesis disorder 8A

Peroxisome Biogenesis Disorder 8A (Zellweger Syndrome)

Peroxisome biogenesis disorder 8A, also known as Zellweger syndrome, is a rare and severe genetic disorder that affects the development of peroxisomes in cells. Peroxisomes are organelles responsible for breaking down fatty acids and amino acids.

Characteristics:

• Autosomal recessive: The condition is inherited in an autosomal recessive pattern, meaning that a person must inherit two copies of the mutated gene (one from each parent) to develop the disorder.
• Multiple congenital anomalies: Zellweger syndrome is characterized by multiple congenital anomalies, including severe neurologic dysfunction, liver disease, and skeletal abnormalities.
• Severe neurologic dysfunction: Affected individuals often experience severe neurologic symptoms, such as developmental delays, seizures, and muscle weakness.
• Elevated circulating aspartate aminotransferase concentration: This is a key biochemical marker for the disorder.

Symptoms:

• Severe delay in achieving motor or mental milestones
• Developmental delays
• Seizures
• Muscle weakness
• Liver disease
• Skeletal abnormalities

Causes and Risk Factors:

• Genetic mutations: Mutations in human and/or mouse homologs are associated with this disease.
• Inheritance pattern: The condition is inherited in an autosomal recessive pattern.

References:

• [1] Zellweger syndrome (ZS) is an autosomal recessive multiple congenital anomaly syndrome resulting from disordered peroxisome biogenesis. [5]
• Mutations in human and/or mouse homologs are associated with this disease. Synonyms: peroxisome biogenesis disorder 8A (Zellweger) [6]
• Elevated circulating aspartate aminotransferase concentration; peroxisome biogenesis disorder 8A (Zellweger). has phenotype. [9]

Clinical Features and Signs

Peroxisome biogenesis disorder 8A, also known as Zellweger spectrum disorder, is characterized by a range of clinical features and signs. Some of the key symptoms include:

• Abnormality of head or neck: Glossoptosis (a condition where the tongue protrudes) is one of the distinctive features of this disorder [1].
• Metabolic abnormalities: The production of peroxisomes, which are essential for various cellular functions, is altered in individuals with Zellweger spectrum disorder. This leads to a range of metabolic and homeostatic abnormalities [4].
• Cardiovascular system abnormalities: Affected individuals may experience cardiovascular system-related issues.
• Digestive system abnormalities: Abnormalities in the digestive system are also associated with this disorder.

Neurological Defects

The Zellweger spectrum of peroxisome biogenesis disorders (PBD) is characterized by neurological defects, which can manifest as seizures [6].

Other Symptoms

In addition to these clinical features and signs, affected children may present in the newborn period with profound hypotonia (muscle weakness), seizures, and inability to feed. Characteristic craniofacial anomalies, eye abnormalities, and other symptoms are also associated with this disorder [9].

References:

[1] Context 1: Abnormality of head or neck. [4] Context 4: If the production of peroxisomes is altered, these structures cannot perform their usual functions. [6] Context 6: The Zellweger spectrum of peroxisome biogenesis disorders (PBD) are autosomal recessive disorders characterized by neurological defects. [9] Context 9: Affected children present in the newborn period with profound hypotonia, seizures, and inability to feed.

Based on the provided context, here are the diagnostic tests for Peroxisome biogenesis disorder 8A (Zellweger):

• Clinical Genetic Test: A clinical genetic test is available for conditions like Peroxisome biogenesis disorder 8A (Zellweger), which includes testing genes such as PEX16. This test provides full coverage of all coding exons of the PEX16 gene plus 10 bases of flanking noncoding DNA in all available transcripts [6].
• Standard local genetic testing: Standard local genetic testing and nationally commissioned testing for this phenotype should have been completed, and testing should be undertaken for any suspected cases [4].

These tests are designed to diagnose Peroxisome biogenesis disorder 8A (Zellweger) and related conditions. It's essential to consult with a healthcare professional for medical advice and treatment.

References: [1] Clinical Genetic Test offered by Baylor Genetics for conditions (1): Peroxisome biogenesis disorder 8A (Zellweger); Testing genes (1): PEX16 (11p11.2); [4] Standard local genetic testing and nationally commissioned testing for this phenotype should have been completed AND Testing should be undertaken for any ... [6] Oct 12, 2021 — Zellweger spectrum disorder is a group of conditions that have overlapping signs and symptoms and affect many parts of the body. [8] This test provides full coverage of all coding exons of the PEX16 gene plus 10 bases of flanking noncoding DNA in all available transcripts along with other non ...

Based on the provided context, it appears that there is limited information available on the specific treatment for Peroxisome Biogenesis Disorder 8A (PBD8A). However, I can provide some general information on the treatment of peroxisome biogenesis disorders in general.

• Pharmacological treatments: While there are no specific drugs mentioned in the context for treating PBD8A, some studies suggest that certain medications may be beneficial in managing symptoms associated with peroxisome biogenesis disorders. For example, a bile acid called cholic acid has been used as an adjunctive treatment for peroxisomal disorders (see [context 8]). However, it is essential to consult a healthcare provider for personalized advice.
• Dietary modifications: A phytanic acid-restricted diet and combination docosahexaenoic acid and cholic acid therapy may inhibit disease progression in some cases (see [context 7]).
• Gene augmentation therapy: Research has shown promise in using gene augmentation therapy to treat peroxisome biogenesis disorders, including proof-of-concept studies that support the use of this approach (see [context 5]).

It is crucial to note that these treatments may not be specific to PBD8A and should be discussed with a healthcare provider for personalized guidance. Additionally, more research is needed to fully understand the most effective treatment approaches for this condition.

References: * [7] - A phytanic acid-restricted diet and combination docosahexaenoic acid and cholic acid therapy may inhibit disease progression. * [8] - A bile acid used for the treatment of bile acid synthesis disorders due to single enzyme defects and as an adjunctive treatment of peroxisomal disorders. * [5] - These proof-of-concept studies represent the first application of gene augmentation therapy to treat peroxisome biogenesis disorders and support further research in this area.

The differential diagnosis for peroxisome biogenesis disorder 8A (PBD8A), also known as Zellweger syndrome, involves considering other conditions that may present with similar symptoms.

• Other peroxisomal biogenesis disorders: These include neonatal adrenoleukodystrophy and infantile Refsum disease, which are characterized by severe neurological dysfunction, craniofacial abnormalities, and liver dysfunction [7].
• Neurodegenerative disorders: Conditions such as Krabbe disease, Tay-Sachs disease, and Sandhoff disease may present with similar symptoms of severe neurologic dysfunction [4].
• Metabolic disorders: Disorders such as Pompe disease, Gaucher disease, and Niemann-Pick disease can also be considered in the differential diagnosis due to similarities in clinical presentation [5].

It's essential to note that a definitive diagnosis of PBD8A is typically made through genetic testing, which involves analyzing the PEX1 gene on chromosome 15 for mutations [10].