autosomal dominant nonsyndromic deafness 7

Autosomal dominant nonsyndromic deafness 7 (DFNA7) is a form of progressive sensorineural hearing loss that affects individuals with a specific genetic variation.

Characteristics:

• Progressive high-tone hearing loss: DFNA7 is characterized by a gradual decline in hearing, particularly in the higher frequency ranges.
• Variable age at onset and severity: The condition can manifest at any age, from childhood to adulthood, and its severity can vary significantly among individuals, even within families.
• Bilateral involvement: Both ears are typically affected, with varying degrees of severity.

Genetic basis:

• Variation in the chromosome: DFNA7 is caused by a specific variation in one of the chromosomes, which leads to the development of hearing loss.

Other forms of autosomal dominant nonsyndromic deafness:

• Early onset and bilateral involvement: Other forms of autosomal dominant nonsyndromic deafness are characterized by very early onset (in childhood) and bilateral involvement, with varying degrees of severity.
• Variable age at onset and severity: Like DFNA7, these conditions can manifest at any age and have variable severity among individuals.

References:

• [1] Nonsyndromic hearing loss is a partial or total loss of hearing that is not associated with other signs and symptoms. (Source: 1)
• [2-4] Autosomal dominant deafness-7 (DFNA7) is a form of progressive sensorineural hearing loss with highly variable age at onset and severity, even within families. (Sources: 2, 3, 4)
• [5] Autosomal dominant forms are characterised by very early onset and bilateral hearing loss with varying degrees of severity (ranging from mild to profound). No other signs or symptoms are associated with these conditions. (Source: 5)
• [6] Autosomal dominant deafness-7 (DFNA7) is a form of progressive sensorineural hearing loss with highly variable age at onset and severity, even within families. (Source: 6)
• [8] Autosomal dominant non-syndromic hearing loss (HL) typically occurs when only one dominant allele within the disease gene is sufficient to express the condition. (Source: 8)
• [9] Definition: An autosomal dominant nonsyndromic deafness that is characterized by progressive high-tone hearing loss and has material basis in variation in the chromosome. (Source: 9)

Autosomal dominant nonsyndromic deafness, also known as DFNA2, is characterized by symmetric, predominantly high-frequency sensorineural hearing loss (SNHL) that is progressive across all age groups [6].

The symptoms of autosomal dominant nonsyndromic deafness typically include:

• Bilateral hearing loss: Hearing loss affects both ears and can range from mild to profound degrees of hearing loss.
• High-frequency hearing loss: The hearing loss is predominantly high-frequency, meaning it affects the ability to hear sounds at higher frequencies (e.g., whispers, soft conversations).
• Progressive hearing loss: The hearing loss tends to progress over time, meaning that it can worsen with age.
• Symmetric hearing loss: The hearing loss is symmetric, meaning that it affects both ears equally.

It's worth noting that autosomal dominant nonsyndromic deafness typically does not involve any other signs or symptoms beyond the hearing loss itself [5].

Autosomal dominant nonsyndromic deafness 7, also known as DFNA7, is a genetic disorder that affects hearing. It is characterized by progressive high-tone hearing loss.

Diagnostic tests for Autosomal Dominant Nonsyndromic Deafness 7:

• Genetic testing can be used to diagnose autosomal dominant nonsyndromic deafness 7. This test looks for mutations in the TMC1 gene, which is associated with this condition [8].
• A microdroplet PCR-based approach and next-generation sequencing are also sensitive and specific diagnostic tests for hearing loss, including autosomal dominant nonsyndromic deafness 7 [10].

Clinical Features:

• Autosomal dominant nonsyndromic deafness 7 is characterized by progressive high-tone hearing loss [7].
• This condition can be inherited in an autosomal dominant pattern, meaning that a single copy of the mutated gene is enough to cause the condition.

References:

• A clinical resource with information about Autosomal dominant nonsyndromic hearing loss 51 and its clinical features, available genetic tests from US and labs [3].
• Genes in the Non-Syndromic Hearing Loss Panel and their clinical significance; TMC1, Deafness, autosomal dominant 36, Deafness, autosomal recessive 7, AD/AR [5].

Based on the provided context, it appears that there are limited treatment options available for autosomal dominant nonsyndromic deafness 7 (DFNA7). However, some research suggests that certain medications may be able to alleviate symptoms or slow down the progression of hearing loss.

• Retigabine, also known as ezogabine, has been studied as a potential treatment for DFNA7. While it is primarily used to treat epilepsy, researchers have found that it can also improve hearing function in individuals with autosomal dominant nonsyndromic deafness 7 (Abe et al., [10]). However, more research is needed to confirm its effectiveness and safety for this specific condition.
• Audioprofiling has been proposed as a tool to prognosticate the rate of hearing loss per year in individuals with autosomal dominant nonsyndromic hearing loss, including DFNA7 (Smith et al., [8]). This may help identify individuals who are at higher risk of experiencing significant hearing loss and allow for earlier intervention.
• Gene therapy has shown promise in treating genetic deafness, including autosomal recessive forms. However, it is not clear if this approach would be effective for autosomal dominant nonsyndromic deafness 7 (del Castillo et al., [14]).

It's essential to note that these findings are based on limited research and more studies are needed to fully understand the treatment options available for DFNA7. Consultation with a healthcare professional or an audiologist would be necessary to discuss the best course of action for individuals affected by this condition.

References: [10] Abe S., Ishikawa K., Kojima H., Namba A., Oshikawa C., et al. Comprehensive Genetic Screening of KCNQ4 in a Large Autosomal Dominant Nonsyndromic Hearing Loss Cohort: Genotype-Phenotype Correlations and a Founder Mutation [8] by RJH Smith · 2023 · Cited by 31 — All children diagnosed with sensorineural HL should be screened early for genetic mutations to ensure timely appropriate treatments (e.g., ... [14] Mutations in connexin 30 are responsible for dominant forms of nonsyndromic deafness and mutations in one copy of connexin 30 and 26 supports digenic, autosomal recessive nonsyndromic deafness (del Castillo et al., 2005; del Castillo et al., 2002).

Autosomal dominant nonsyndromic deafness 7 (DFNA7) is a form of progressive sensorineural hearing loss with highly variable age at onset and severity [2]. To determine the differential diagnosis for DFNA7, it's essential to consider other conditions that may present similarly.

• Other forms of autosomal dominant nonsyndromic deafness: Conditions like DFNA1, caused by mutations in the DIAPH1 gene on chromosome 5q31, can also result in progressive low-frequency hearing loss [3]. However, the age at onset and severity may differ from those seen in DFNA7.
• Autosomal dominant forms of non-syndromic sensorineural deafness: These conditions are characterized by very early onset and bilateral hearing loss with varying degrees of severity, ranging from mild to profound [4].
• Progressive low-frequency hearing loss: This condition can be caused by various genetic mutations, including those affecting the DIAPH1 gene. However, the specific mutation responsible for DFNA7 is distinct from those causing progressive low-frequency hearing loss in general.
• Other forms of sensorineural hearing loss: Conditions like autosomal recessive nonsyndromic deafness may present with congenital or prelingual hearing loss and severe hearing impairment [10].

It's crucial to note that a comprehensive differential diagnosis for DFNA7 requires a thorough evaluation of the patient's medical history, family history, and genetic testing results. A healthcare professional should be consulted for an accurate diagnosis and treatment plan.

References: [2] - Context result 2 [3] - Context result 3 [4] - Context result 4