autosomal recessive nonsyndromic deafness 18B

Autosomal recessive nonsyndromic deafness 18B, also known as DFNB18A, is a form of hearing impairment that affects one or both ears. It is caused by a mutation in the OTOG gene [3]. This type of deafness is inherited in an autosomal recessive pattern, meaning that a person must inherit two copies of the mutated gene (one from each parent) to express the condition [4].

Individuals with autosomal recessive nonsyndromic deafness 18B may experience moderate hearing impairment, which can be accompanied by vestibular symptoms [6]. The condition is often characterized by prelingual deafness, meaning that it manifests before speech development [9].

It's worth noting that non-syndromic hearing loss, including autosomal recessive nonsyndromic deafness 18B, can also be inherited in other patterns such as autosomal dominant, X-linked, and mitochondrial [8].

Autosomal recessive nonsyndromic deafness 18B, also known as DFNB18A, is a form of hearing loss caused by a mutation in the harmonin gene (605242). This condition is inherited in an autosomal recessive pattern and affects the ability to hear.

Degrees of Hearing Loss

• The degree of hearing loss can range from mild to profound, with some individuals experiencing difficulty understanding soft speech while others may be unable to hear even very loud noises [1].
• In general, autosomal recessive nonsyndromic hearing loss is prelingual and severe to profound, with a spectrum of degrees of hearing impairment [8].

Clinical Signs and Symptoms

• The primary symptom of autosomal recessive nonsyndromic deafness 18B is hearing loss, which can be unilateral or bilateral.
• There are no other associated signs and symptoms, as this condition is non-syndromic in nature [6].
• Some individuals may experience vertigo, but this is not a universal symptom [5].

Genetic Cause

• Autosomal recessive nonsyndromic deafness 18B is caused by a mutation in the harmonin gene (605242), which maps to chromosome 11p15 [3].
• This genetic mutation leads to hearing loss due to its impact on the inner ear's ability to process sound.

Inheritance Pattern

• Autosomal recessive nonsyndromic deafness 18B is inherited in an autosomal recessive pattern, meaning that an individual must inherit two copies of the mutated gene (one from each parent) to express the condition [2].

It's essential to note that this information is specific to autosomal recessive nonsyndromic deafness 18B and may not be applicable to other forms of hearing loss or genetic conditions.

References: [1] Context result 1 [2] Context result 2 [3] Context result 3 [5] Context result 5 [6] Context result 6 [8] Context result 8

Autosomal recessive nonsyndromic deafness 18B, also known as DFNB18A, is a form of hearing loss caused by mutations in the harmonin gene. The diagnostic tests for this condition are crucial for accurate diagnosis and management.

Diagnostic Tests:

• Genetic testing: This involves analyzing the DNA sequence of the harmonin gene to identify any mutations that may be causing the deafness. [4]
• Clinical genetic test offered by Intergen: This test assesses the presence of mutations in the OTOG gene, which is associated with autosomal recessive nonsyndromic hearing loss 18B. [1]

Other Relevant Information:

• Autosomal recessive nonsyndromic deafness can be classified into different patterns of inheritance, including autosomal recessive, autosomal dominant, X-linked, and mitochondrial. [7]
• Non-syndromic hearing loss generally follows simple Mendelian inheritance and is predominantly transmitted as an autosomal recessive trait (75-80%). [9]

Diagnostic Yield:

• A study by S Alkhidir in 2024 reported a diagnostic yield of 60% for targeted familial testing and 50% for gene panel testing. [8]

Please note that these tests are not exhaustive, and other diagnostic methods may be employed depending on the individual case.

References: [1] Clinical Genetic Test offered by Intergen [4] A form of autosomal recessive deafness designated DFNB18A (602092), which also maps to chromosome 11p15, is caused by mutation in the harmonin gene (605242). [7] Non-syndromic hearing loss is inherited in one of the following patterns: autosomal recessive, autosomal dominant, X-linked, and mitochondrial. [8] The diagnostic yield for targeted familial testing was 60% (n = 3 patients) and for gene panel was 50% (n = 5). [9] Non-syndromic hearing loss (NSHL) generally follows simple Mendelian inheritance and is predominantly transmitted as an autosomal recessive trait (75–80%).

Based on the provided context, it appears that there are limited information available about drug treatment for autosomal recessive nonsyndromic deafness 18B.

However, I found some relevant information in search results:

• There is no mention of any specific drug treatment for autosomal recessive nonsyndromic deafness 18B in the provided context.
• However, an interim analysis of a single-arm trial in 5 children with hereditary deafness shows that binaural AAV gene therapy is safe and leads to hearing improvement up to 13–26 weeks of follow-up [4].
• The etiology of sensorineural hearing loss is heavily influenced by genetic mutations, with approximately 80% of cases attributed to genetic causes and only 20% to environmental factors. Over 100 non-syndromic deafness genes have been identified in humans thus far [7].

It's worth noting that autosomal recessive nonsyndromic deafness 18B is caused by mutation in the OTOG gene, but there is no information available about any specific drug treatment for this condition.

However, it's also mentioned that ClinVar archives and aggregates information about relationships among variation and human health [9], which might be a useful resource to find more information about potential treatments or therapies for autosomal recessive nonsyndromic deafness 18B.

In summary, while there is no specific drug treatment available for autosomal recessive nonsyndromic deafness 18B, gene therapy and other emerging technologies may hold promise for future treatments. However, more research is needed to fully understand the potential benefits and limitations of these approaches.

References: [4] - An interim analysis of a single-arm trial in 5 children with hereditary deafness shows that binaural AAV gene therapy is safe and leads to hearing improvement up to 13–26 weeks of follow-up. [7] - The etiology of sensorineural hearing loss is heavily influenced by genetic mutations, with approximately 80% of cases attributed to genetic causes and only 20% to environmental factors. Over 100 non-syndromic deafness genes have been identified in humans thus far. [9] - ClinVar archives and aggregates information about relationships among variation and human health.

Autosomal recessive nonsyndromic deafness (ARNSHL) can be challenging to diagnose, as it often presents with hearing loss as the only symptom. However, there are some key factors and genes that can help in making a differential diagnosis.

Genetic Causes

The most common genetic cause of ARNSHL is mutations in one of 42 genes, which have been identified in individuals with autosomal recessive nonsyndromic hearing loss (ARNSHL) [1]. Some of the notable genes associated with ARNSHL include:

• GJB2: Mutations in the GJB2 gene are the most common cause of congenital severe-to-profound hearing loss, accounting for approximately 50% of cases [3].
• STRC: Mutations in the STRC gene are a common cause of moderate autosomal recessive nonsyndromic hearing loss [2].

Clinical Features

While ARNSHL is characterized by hearing loss as the only symptom, there may be some subtle clinical features that can aid in diagnosis. These include:

• Bilateral and symmetric hearing loss
• Congenital or prelingual onset of hearing loss
• Severe to profound hearing loss

Differential Diagnosis

ARNSHL should be differentiated from other forms of hearing loss, including:

• Syndromic deafness: This is characterized by hearing loss associated with other symptoms and signs.
• Autosomal dominant nonsyndromic hearing loss: This is a rare form of hearing loss that follows an autosomal dominant inheritance pattern.

Genetic Testing

Genetic testing can be performed to identify mutations in the genes associated with ARNSHL. A hearing loss multigene panel, which includes all genes implicated in nonsyndromic hearing loss and disorders that mimic nonsyndromic hearing loss, is most likely to identify the genetic cause of the condition [10].

References

[1] More than 700 different mutations have been identified in one of 42 genes in individuals with autosomal recessive nonsyndromic hearing loss (ARNSHL) [14]. [2] The