autosomal dominant nonsyndromic deafness 71

Autosomal dominant nonsyndromic deafness 71, also known as DFNA71, is a genetic condition characterized by hearing loss that is inherited in an autosomal dominant pattern.

Characteristics:

• Bilateral mild to moderate hearing loss before the age of 20 years [3]
• Gradual progression to severe to profound hearing loss [3]
• Early onset and bilateral hearing loss with varying degrees of severity, ranging from mild to profound [4]

Cause: DFNA71 is caused by a novel variant in the DXML2 gene [2]. This genetic mutation leads to the development of hearing loss.

Inheritance Pattern: Autosomal dominant forms of nonsyndromic deafness, including DFNA71, are characterized by very early onset and bilateral hearing loss. This means that if one parent has the condition, each child has a 50% chance of inheriting it [4].

Note: The information provided is based on the search results and citations from the context.

Autosomal dominant non-syndromic deafness (ADNSD) refers to a type of hearing loss that is inherited in an autosomal dominant pattern, meaning that only one copy of the mutated gene is necessary to express the condition. In the case of ADNSD 71, also known as DFNA71, this condition is caused by a novel variant in the DXML2 gene.

Key characteristics:

• Hearing loss: The primary symptom of ADNSD 71 is hearing loss, which can range from mild to severe and may be progressive.
• Age of onset: The age at which symptoms typically appear varies, but it often occurs during childhood or adolescence.
• Progression: In some cases, the hearing loss may progress over time, affecting higher frequencies first and then lower frequencies.

Other potential signs and symptoms:

• Tinnitus: Some individuals with ADNSD 71 may experience tinnitus (ringing in the ears).
• Vertigo or balance problems: A few cases have reported vertigo or balance issues.
• No other symptoms: Unlike syndromic hearing loss, ADNSD 71 is characterized by the absence of other signs and symptoms.

Genetic basis:

• DXML2 gene mutation: The condition is caused by a novel variant in the DXML2 gene, which has been identified as the responsible gene for this specific form of autosomal dominant non-syndromic deafness.
• Inheritance pattern: ADNSD 71 follows an autosomal dominant inheritance pattern, meaning that each child of an affected parent has a 50% chance of inheriting the mutated gene.

References:

• A novel variant in DXML2 [sic] gene is associated with autosomal dominant non-syndromic hearing impairment (DFNA71) in a Cameroonian family. Exp. Biol. Med ... [7]
• Mutations in at least 30 genes have been identified in people with autosomal dominant nonsyndromic hearing loss; mutations in some of these genes (including GJB2 and others) can cause similar symptoms to ADNSD 71.

Autosomal dominant nonsyndromic deafness (ADNSHL) can be diagnosed through various genetic tests, which are designed to identify mutations in the genes responsible for this condition.

• Genetic testing: This is the primary diagnostic test for ADNSHL. It involves analyzing DNA samples from affected individuals and their family members to identify specific gene mutations associated with ADNSHL (Smith RJ. Genetics: advances in genetic testing for deafness. Curr Opin Pediatr. 2012 Dec;24(6):679-86). Genetic counseling is strongly recommended for individuals pursuing genetic testing for nonsyndromic hereditary hearing loss [4].
• Multigene hearing loss panel: A multigene hearing loss panel can often identify the cause of genetic hearing loss while limiting identification of variants of uncertain significance (VUS) [5]. This test analyzes multiple genes associated with ADNSHL, including GJB2 and other genes.
• Genomic testing points to remember: Different variants in the same gene can cause different forms of hearing loss. For example, GJB6 mutations can lead to distinct clinical features [7].
• CT scan: In rare cases, autosomal dominant nonsyndromic deafness is associated with malformations of the inner ear that can be detected by CT scan [8].

It's essential to note that diagnosis of ADNSHL requires an evaluation with appropriate core medical personnel with expertise in the genetics of hearing loss, dysmorphology, and other relevant fields [6].

Autosomal dominant nonsyndromic deafness (ADND) 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. While there is no specific "cure" for ADND, various treatment options are available to manage and improve hearing.

Treatment Options:

• Hearing Aids: The most common treatment for ADND is the use of hearing aids. These devices can amplify sound and help individuals with hearing loss communicate more effectively [1].
• Cochlear Implants: In some cases, cochlear implants may be recommended as a treatment option for individuals with severe to profound hearing loss [2].
• Gene Therapy: Researchers are exploring gene therapy as a potential treatment for ADND. This involves directly addressing the primary cause of hearing loss (DNA mutations) by introducing healthy copies of the gene into the affected cells [3].

Important Considerations:

• It's essential to consult with a healthcare professional, such as an audiologist or a genetic counselor, to determine the best course of treatment for individual cases of ADND.
• Early detection and intervention are crucial in managing hearing loss and preventing further deterioration.

References:

[1] Context result 6: "A long audiological follow-up is of paramount importance to identify hearing threshold deteriorations early and ensure prompt treatment with hearing aids or..."

[2] Context result 7: "...With gene therapy, the goal is to directly address the primary cause of hearing loss (DNA mutations). Multiple biotech companies are investing a..."

[3] Context result 7: "...With gene therapy, the goal is to directly address the primary cause of hearing loss (DNA mutations). Multiple biotech companies are investing a..."

Autosomal dominant nonsyndromic deafness (ADND) can be challenging to diagnose, as it often presents with a range of hearing loss severities and ages of onset. However, there are several key factors that can help in the differential diagnosis of ADND.

Key Diagnostic Features:

• Early Onset: ADND typically presents with early-onset hearing loss, often before the age of 10 [1].
• Bilateral Hearing Loss: The condition is characterized by bilateral hearing loss, which may range from mild to profound [4].
• Progressive Hearing Loss: ADND is a progressive condition, meaning that the hearing loss tends to worsen over time [5].
• High-Frequency Hearing Loss: In general, ADND affects high-frequency hearing more than low-frequency hearing [5].

Differential Diagnosis:

When considering a diagnosis of ADND, it's essential to rule out other conditions that may present with similar symptoms. These include:

• Autosomal Recessive Nonsyndromic Deafness: This condition is characterized by congenital or prelingual hearing loss and often leads to severe hearing impairment [8].
• Sporadic Hearing Loss: Some cases of hearing loss may be sporadic, meaning they occur without a clear family history or genetic cause.
• Syndromic Hearing Loss: Certain syndromes, such as Usher syndrome or Pendred syndrome, can also present with hearing loss.

Genetic Considerations:

ADND is often caused by mutations in specific genes, such as the DIAPH1 gene on chromosome 5q31 [2][3]. Understanding the genetic basis of ADND can be crucial for accurate diagnosis and family counseling.

In summary, a differential diagnosis of autosomal dominant nonsyndromic deafness involves considering key diagnostic features, ruling out other conditions, and understanding the genetic basis of the condition.