autosomal dominant nonsyndromic deafness 65

Autosomal dominant nonsyndromic deafness 65, also known as DFNA65, is a form of hearing loss that is inherited in an autosomal dominant pattern.

• Inheritance: This type of hearing loss is caused by mutations in one of the two copies of the responsible gene. A single copy of the mutated gene is sufficient to cause the condition.
• Prevalence: The prevalence of DFNA65 is not well established, but it is considered a rare form of autosomal dominant nonsyndromic deafness.

Characteristics

• Age of onset: The age of onset for DFNA65 can vary, but it typically occurs in adulthood.
• Type of hearing loss: This type of hearing loss is characterized by progressive sensorineural hearing loss, which means that the inner ear's ability to detect sound is gradually impaired over time.
• Degree of hearing loss: The degree of hearing loss associated with DFNA65 can range from mild to severe.

Genetic basis

• Responsible gene: The responsible gene for DFNA65 has not been identified yet, but it is believed to be a novel gene that plays a crucial role in the development and function of the inner ear.
• Inheritance pattern: As mentioned earlier, this type of hearing loss is inherited in an autosomal dominant pattern, meaning that a single copy of the mutated gene is sufficient to cause the condition.

References

• The information provided above is based on general knowledge about autosomal dominant nonsyndromic deafness and may not be specific to DFNA65.
• Further research is needed to determine the exact characteristics and genetic basis of this type of hearing loss.

Autosomal dominant nonsyndromic deafness, also known as DFNA hearing loss, typically presents with very early onset and bilateral hearing loss with varying degrees of severity [4]. The hearing loss can range from mild to profound degrees [1].

The signs and symptoms of autosomal dominant nonsyndromic deafness are primarily related to hearing loss. There are no other associated signs or symptoms [5]. The condition is characterized by:

• Bilateral hearing loss: Hearing loss affects both ears, with varying degrees of severity.
• Early onset: Hearing loss typically begins in early childhood, often before the age of 10 [8].
• Progressive hearing loss: The hearing loss can progress over time, affecting higher frequencies first and later involving middle and high frequencies [9].

It's essential to note that autosomal dominant nonsyndromic deafness is a genetic condition, and the inheritance pattern is autosomal dominant. This means that only one copy of the altered gene in each cell is sufficient to result in hearing loss [2].

Autosomal dominant nonsyndromic deafness (ADNSHL) is a form of hearing loss that is inherited in an autosomal dominant pattern, meaning that a single copy of the mutated gene is enough to cause the condition. Diagnostic tests for ADNSHL are crucial for accurate diagnosis and genetic counseling.

Diagnostic Tests:

• Exome sequencing: This is a comprehensive test that analyzes all protein-coding genes (exons) in the genome. It can identify mutations in any of the 30+ genes associated with ADNSHL [1].
• Genome sequencing: While not as commonly used, genome sequencing can also be employed to diagnose ADNSHL by analyzing the entire genome for mutations [1].
• Exome array: This test is similar to exome sequencing but uses a microarray to analyze specific regions of the genome. It may be considered if exome sequencing is not available or feasible [1].

Clinical Considerations:

• Genetic counseling is strongly recommended for individuals pursuing genetic testing for ADNSHL, as it can help them understand their risk and make informed decisions about testing and family planning [4].
• A diagnosis of ADNSHL requires an evaluation with appropriate core medical personnel with expertise in the genetics of hearing loss, dysmorphology, and other relevant areas [6].

Important Notes:

• Different variants in the same gene can cause different forms of hearing loss. For example, GJB6 mutations may lead to different types of hearing loss [10].
• Thyroid gland disease may also be associated with ADNSHL in rare cases, which can be detected by CT scans [7].

References:

[1] RJH Smith (2018) - Exome sequencing is most commonly used; genome sequencing is also possible. [4] Genetic counseling is strongly recommended for individuals pursuing genetic testing for nonsyndromic hereditary hearing loss. [6] Jan 1, 2024 - Diagnosis of NSHL requires an evaluation with appropriate core medical personnel with expertise in the genetics of hearing loss, dysmorphology, ... [7] This form of deafness is always associated with malformations of the inner ear that can be detected by CT scan. In rare cases, thyroid gland disease may also be ... [10] There are two important genomic testing points to remember: different variants in the same gene can cause different forms of hearing loss – for example, GJB6 ...

Based on the provided context, it appears that there are no specific drug treatments mentioned for autosomal dominant nonsyndromic deafness.

However, gene therapy is being explored as a potential treatment option for this condition. According to search result [7], "With gene therapy, the goal is to directly address the primary cause of hearing loss (DNA mutations)". Additionally, search result [11] mentions that gene therapy has successfully restored hearing function in >20 types of genetic deafness model mice and can almost completely cure patients with hereditary autosomal recessive deafness 9 (DFNB9) caused by the OTOFERLIN (OTOF) mutation.

It's worth noting that the context also mentions that a long audiological follow-up is of paramount importance to identify hearing threshold deteriorations early and ensure prompt treatment with hearing aids or other interventions [6]. However, this does not specifically mention drug treatments for autosomal dominant nonsyndromic deafness.

Therefore, based on the available information, it seems that gene therapy may be a potential area of research for treating autosomal dominant nonsyndromic deafness, but there are no specific drug treatments mentioned in the provided context.

Autosomal dominant nonsyndromic deafness (ADNSHL) is a type of hearing loss that is inherited in an autosomal dominant pattern, meaning that a single copy of the mutated gene is enough to cause the condition. The differential diagnosis for ADNSHL involves considering various genetic and environmental factors that may contribute to the development of hearing loss.

Genetic Factors

• DFNA1: This is one of the most common forms of autosomal dominant nonsyndromic deafness, caused by mutations in the DIAPH1 gene on chromosome 5q31. It leads to progressive low-frequency hearing loss, resulting in a profound degree of hearing impairment [4].
• DFNA2: This form is associated with mutations in the KCNQ4 gene and is characterized by early onset and bilateral hearing loss with varying degrees of severity [1].
• Other genes: Over 120 genes have been identified as causing non-syndromic hearing loss, including autosomal dominant forms. These genes can be inherited from a parent who has hearing loss or occur de novo (spontaneously) in the individual [6].

Environmental and Other Factors

• Age of onset: Autosomal dominant nonsyndromic deafness often presents with early onset, typically before the age of 10 [3].
• Progression: The condition is usually progressive, meaning that hearing loss worsens over time.
• Bilateral involvement: Hearing loss in ADNSHL is typically bilateral (affecting both ears) and can range from mild to profound.

Differential Diagnosis

When considering a diagnosis of autosomal dominant nonsyndromic deafness, it's essential to rule out other conditions that may cause similar symptoms. These include:

• Autosomal recessive non-syndromic hearing loss: This is the most common form of inherited hearing loss and is caused by mutations in genes such as GJB2 [9].
• Sensory neural hearing loss: This type of hearing loss can be caused by various factors, including infections, toxins, or trauma to the ear.
• Mixed hearing loss: This condition involves a combination of conductive and sensorineural hearing loss.

In conclusion, autosomal dominant nonsyndromic deafness is a complex condition that requires careful consideration of genetic and environmental factors. A thorough differential diagnosis is essential to rule out other conditions that may cause similar symptoms.