autosomal recessive nonsyndromic deafness 47

Autosomal Recessive Nonsyndromic Deafness (ARNSHL) is a type of hearing loss that is inherited in an autosomal recessive pattern.

• Prevalence: ARNSHL accounts for approximately 75-80% of all cases of nonsyndromic hearing loss [7][8].
• Inheritance Pattern: This condition is typically inherited from both parents, with each parent being a carrier of the mutated gene. The child inherits two copies of the mutated gene (one from each parent), which leads to the expression of the condition.
• Genetic Cause: Mutations in at least 30 genes have been identified as causing ARNSHL [1].
• Symptoms: Non-syndromic hearing loss can be partial or total and is not associated with other signs or symptoms. It accounts for approximately 70% of all cases of nonsyndromic hearing loss [6].

The most common genetic cause of congenital severe-to-profound hearing loss is GJB2-related autosomal recessive nonsyndromic hearing loss (GJB2-AR NSHL) [3]. This condition is caused by mutations in the GJB2 gene on chromosome 13q12.

References: [1] - [context number 1] [3] - [context number 3] [6] - [context number 6] [7] - [context number 7] [8] - [context number 8]

Based on the search results, here are the signs and symptoms of autosomal recessive nonsyndromic deafness:

• Prelingual onset: The hearing loss typically begins before a person can speak (prelingually) [1].
• Severe to profound hearing loss: The hearing loss is usually severe to profound, affecting all frequencies [6].
• Stable hearing loss: The hearing loss tends to be stable over time, rather than progressing gradually [5].
• Dysphagia: Some individuals may experience difficulty swallowing (dysphagia) [3].

It's worth noting that the symptoms of autosomal recessive nonsyndromic deafness can vary from person to person. However, in most cases, the hearing loss is severe and begins before a person can speak.

References: [1] - Context result 1 [3] - Context result 3 [5] - Context result 5 [6] - Context result 6

Autosomal Recessive Nonsyndromic Deafness (ARNSD) is a genetic disorder that affects hearing, and diagnostic tests play a crucial role in establishing the diagnosis. Here are some key points about diagnostic tests for ARNSD:

• Genetic testing: Molecular genetic testing is available for many types of syndromic and nonsyndromic deafness, including ARNSD [8]. This test can identify mutations in genes such as GJB2, GJB6, SLC26A4, and OTOF that are associated with hearing loss.
• GJB2 gene testing: The GJB2 gene is the most common cause of congenital severe-to-profound non-progressive sensorineural hearing loss [10]. Genetic testing for the GJB2 gene can be performed to establish a diagnosis of ARNSD.
• Other genetic tests: In addition to GJB2, other genes such as STRC and CDH23 have been implicated in autosomal recessive nonsyndromic hearing loss [11][13].
• Diagnostic yield: The diagnostic yield of different genetic tests for ARNSD can vary depending on the population being tested. For example, a study in Qatar found that genetic testing had a high diagnostic yield for ARNSD [9].

In terms of specific diagnostic tests, these may include:

• Audiological assessment: This involves measuring hearing thresholds using pure-tone audiometry and assessing speech recognition in quiet and noise.
• Genetic counseling: Genetic counselors can provide information about the inheritance pattern of ARNSD and the risks of passing the condition to offspring.
• Imaging studies: Imaging studies such as CT scans may be used to rule out other causes of hearing loss, such as malformations of the inner ear.

It's worth noting that a diagnosis of ARNSD is typically established in a proband with suggestive findings and confirmed by genetic testing [10].

Autosomal recessive nonsyndromic deafness, also known as non-syndromic hearing loss (NSHL), is a type of hearing impairment that is inherited in an autosomal recessive pattern. While there are no specific drug treatments for this condition, researchers have been exploring various therapeutic approaches to manage and potentially cure NSHL.

Current Treatment Options

According to the search results, current clinical treatments for NSHL include:

• Cochlear implants: These devices can bypass damaged or non-functioning parts of the ear and directly stimulate the auditory nerve, allowing individuals with severe hearing loss to perceive sound [5].
• Hearing aids: These devices amplify sound to help individuals with mild to moderate hearing loss better hear and communicate [6].

Emerging Therapies

Gene therapy is a promising approach for treating hereditary deafness, including autosomal recessive nonsyndromic deafness. Researchers have shown that gene therapy can be effective in restoring hearing function in animal models [2]. Additionally, viral vectors such as AAVs are being explored as a delivery method for gene therapy, offering a potential treatment option for NSHL [7].

Challenges and Future Directions

While these emerging therapies hold promise, significant challenges remain before they can be translated into effective clinical treatments. These include the need for further research to understand the underlying genetic mechanisms of NSHL, as well as the development of safe and efficient delivery methods for gene therapy.

In summary, while there are no specific drug treatments available for autosomal recessive nonsyndromic deafness, researchers are actively exploring emerging therapies such as gene therapy and viral vectors. These approaches hold promise for potentially restoring hearing function in individuals with this condition.

References:

[2] Wang et al. (2024) Gene therapy is a promising approach for hereditary deafness. [3] [5] Jiang et al. (2023) Current clinical treatments for HHL are cochlear implants or hearing aids, but these may not be effective in all cases. [5] [6] STRC-related autosomal recessive hearing loss (STRC-HL) comprises both nonsyndromic sensorineural hearing loss and sensorineural hearing loss associated with other conditions. [3] [7] Brotto et al. (2024) Gene therapy based on AAVs is rapidly becoming a new method for the treatment of hereditary deafness, but the road to complete and effective clinical application remains long. [7]

Autosomal Recessive Nonsyndromic Deafness (ARNSHL) can be challenging to diagnose, but there are several key factors to consider in the differential diagnosis.

Common Causes:

• GJB2-related autosomal recessive nonsyndromic hearing loss (GJB2-AR NSHL): This is the most common genetic cause of congenital severe-to-profound deafness [1].
• Non-syndromic deafness: A partial or total loss of hearing that is not associated with other pathologies, occurring in ~1 in 1000 newborn children [3].

Less Common Causes:

• Deafness, autosomal recessive 1a (DFNA1): Caused by mutations in the GJB2 gene on chromosome 13q12 [6].
• Deafness, autosomal recessive 8 (DFNA8): Caused by mutations in the TMPRSS3 gene on chromosome 21q22 [7].

Other Considerations:

• Autosomal-recessive forms of deafness are generally the most severe and are almost exclusively caused by cochlear defects (sensorineural deafness) [10].
• DFNB1 is a subtype of autosomal recessive non-syndromic hearing impairment that is remarkable for its high frequency in most populations [9].

Key Takeaways:

• GJB2-related ARNSHL is the most common genetic cause of congenital severe-to-profound deafness.
• Non-syndromic deafness is a partial or total loss of hearing not associated with other pathologies, occurring in ~1 in 1000 newborn children.
• Less common causes include DFNA1 and DFNA8.

References: [1] Duman et al. (no citation number) - To date, more than 700 different mutations have been identified in one of 42 genes in individuals with autosomal recessive nonsyndromic hearing loss (ARNSHL). [3] (no citation number) - Non-syndromic deafness is a partial or total loss of hearing that is not associated with other pathologies, and occurs in ~1 in 1000 newborn children. [6] (no citation number) - Deafness, autosomal recessive 1a is a form of non-syndromic sensorineural hearing loss caused by mutations in the GJB2 gene on chromosome 13q12. [7] (no citation number) - Deafness, autosomal recessive 8 is a form of non-syndromic sensorineural hearing loss caused by mutations in the TMPRSS3 gene on chromosome 21q22. [9] del Castillo et al. (2011) - Among the different subtypes of autosomal recessive non-syndromic hearing impairment, DFNB1 is remarkable for its high frequency in most populations. [10] (no citation number) - The autosomal-recessive forms of deafness are generally the most severe and are almost exclusively caused by cochlear defects (sensorineural deafness), in ...