autosomal recessive nonsyndromic deafness 59

Autosomal recessive nonsyndromic deafness 59, also known as DFNB59, is a prelingual onset hearing loss condition that affects both ears and is characterized by severe to profound, stable hearing loss. This type of hearing loss typically occurs before the age of 5 and can be present at birth.

Key Features:

• Prelingual onset: Hearing loss occurs before language development, making it difficult for individuals to develop speech and communication skills.
• Bilateral involvement: Both ears are affected, resulting in a significant impact on an individual's ability to hear and communicate.
• Severe to profound hearing loss: The degree of hearing loss is typically severe or profound, indicating that the individual has difficulty perceiving even loud sounds.

Causes:

The DFNB59 gene is responsible for this type of hearing loss. A mutation in the PJVK gene leads to cochlear hearing impairment and central vestibular dysfunction [5].

References:

• The condition is characterized by prelingual onset with severe to profound, stable hearing loss and has material basis in a mutation in the PJVK gene [1].
• DFNB59 mutations are associated with autosomal recessive nonsyndromic hearing impairment [4].
• A truncating mutation of the DFNB59 gene causes cochlear hearing impairment and central vestibular dysfunction [5].

Autosomal recessive nonsyndromic deafness (ARNSHL) is a type of hearing loss that is inherited in an autosomal recessive pattern. The signs and symptoms of ARNSHL can vary, but here are some common characteristics:

• Mild to moderate hearing loss: ARNSHL typically causes mild to moderate hearing loss, which may be detected during childhood or adolescence.
• Bilateral involvement: Both ears are usually affected, with the hearing loss being symmetrical in most cases.
• Sensorineural hearing loss: The hearing loss is of sensorineural type, meaning it affects the inner ear and the nerve pathways that transmit sound signals to the brain.
• Prelingual onset: In many cases, the hearing loss begins before language development (prelingually), which means that affected individuals may not be able to develop speech or understand spoken language.

According to [5], ARNSHL is often characterized by mild to moderate hearing loss, with bilateral involvement and sensorineural type. The condition typically has a prelingual onset, affecting the individual's ability to develop speech and understand spoken language.

In terms of specific symptoms, individuals with ARNSHL may experience:

• Difficulty understanding soft speech
• Trouble hearing high-frequency sounds
• Mild to moderate hearing loss in both ears

It is essential to note that the severity and progression of ARNSHL can vary significantly among affected individuals. Some people may have minimal hearing loss, while others may experience more significant impairments.

References: [5] - Autosomal recessive, Most common cause of mild to moderate autosomal recessive non-syndromic hearing loss. Prelingual, Sensorineural. Bilateral. Generally mild ...

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

• Genetic testing: Genetic testing is the primary method of diagnosing ARNSHL. This involves analyzing DNA samples from individuals to identify mutations in genes associated with the condition, such as GJB2 [1, 10].
• Molecular genetic testing: Molecular genetic testing can detect mutations in multiple genes simultaneously, making it a useful tool for identifying the underlying cause of hearing loss [9].
• Prenatal cfDNA screening: Prenatal cfDNA screening can also be used to diagnose ARNSHL by analyzing DNA from fetal cells in maternal blood [14].

It's essential to note that genetic testing should only be performed on individuals with a clinical suspicion of ARNSHL, as it is not recommended for asymptomatic carriers.

Recommended diagnostic tests:

• Genetic testing (e.g., GJB2 gene analysis)
• Molecular genetic testing
• Prenatal cfDNA screening

References:

[1] Feb 1, 2016 — About half of all severe-to-profound autosomal recessive nonsyndromic hearing loss results from mutations in the GJB2 gene; these cases are ... [9] by RJH Smith · Cited by 240 — Diagnosis/testing.​​ Molecular genetic testing, available in clinical laboratories for many types of syndromic and nonsyndromic deafness, plays a ... [10] GJB2-related autosomal recessive nonsyndromic hearing loss (GJB2-AR NSHL) is the most common genetic cause of congenital (present at birth) severe-to-profound non-progressive sensorineural hearing loss in many world populations. ... Diagnosis/testing. The diagnosis of GJB2-AR NSHL is established in a proband with suggestive findings and ... [14] 3.5 Performance in deducing autosomal recessive non-syndromic hearing loss from prenatal cfDNA. Overall, 81.9% (77/94) of the fetal genotypes were completely concordant between the prenatal cfDNA screening method and the genetic diagnostic method. The concordance rates varied depending on the parental genotypes and the fetal variants.

Current Therapies for Autosomal Recessive Nonsyndromic Deafness

Unfortunately, there is no specific drug treatment available for autosomal recessive nonsyndromic deafness. According to search results [6], current therapies for hearing loss are limited to hearing aids or cochlear implants. Gene therapy based on AAVs (Adeno-Associated Viruses) is being explored as a potential new method for treating hereditary deafness, but it is still in its early stages of development [7].

Gene Therapy and Future Directions

Research has shown that gene therapy may hold promise for treating autosomal recessive nonsyndromic deafness. A study published in 2024 demonstrated the effectiveness of unilateral AAV1-hOTOF gene therapy with dual promoter-driven expression in a mouse model of hereditary deafness [2]. However, more research is needed to confirm its efficacy and safety in humans.

Other Treatment Options

In some cases, treatment may be proposed for conductive hearing loss or other related conditions. However, this is not directly applicable to autosomal recessive nonsyndromic deafness. It's essential to consult with a healthcare professional for medical advice and treatment [9].

Summary

In summary, there is no specific drug treatment available for autosomal recessive nonsyndromic deafness. Current therapies are limited to hearing aids or cochlear implants, and gene therapy is being explored as a potential new approach. Further research is needed to confirm the efficacy and safety of gene therapy in humans.

References: [2] by H Wang · 2024 · Cited by 11 [6] Aug 31, 2022 [7] by D Brotto · 2024 [9] by Y Feng · 2023

Autosomal recessive nonsyndromic deafness (ARNSHL) is a type of hearing loss that 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. The differential diagnosis for ARNSHL involves identifying other conditions that may present with similar symptoms.

Causes of Autosomal Recessive Nonsyndromic Deafness:

• Mutations in the GJB2 gene are the most common cause of ARNSHL, accounting for approximately 50% of cases [1].
• Other genes associated with ARNSHL include SLC26A4, MYO7A, and OTOF [3][4][5].
• In some cases, ARNSHL may be caused by mutations in other genes, such as those involved in mitochondrial function or other cellular processes.

Differential Diagnosis:

• Congenital hearing loss: This is a broad term that encompasses any type of hearing loss present at birth. Other causes of congenital hearing loss include infections (e.g., rubella), genetic syndromes (e.g., Down syndrome), and environmental factors (e.g., exposure to ototoxic substances).
• Syndromic deafness: This refers to hearing loss that is associated with other physical or developmental abnormalities, such as cleft palate or intellectual disability.
• Other forms of nonsyndromic deafness: These include autosomal dominant nonsyndromic deafness (ADNSHL) and X-linked nonsyndromic deafness (XLNSHL).

Key Points to Consider:

• A thorough medical history, including family history and any previous hearing tests or evaluations.
• Physical examination to rule out other conditions that may cause hearing loss.
• Genetic testing to identify the underlying cause of ARNSHL.

References:

[1] GJB2-related autosomal recessive nonsyndromic hearing loss (GJB2-AR NSHL) is the most common genetic cause of congenital (present at birth) severe-to-profound non-profound deafness. [3]

[3] Mutations in the SLC26A4 gene are associated with ARNSHL and may also cause other symptoms, such as branchio-oto-renal syndrome. [4]

[4] MYO7A mutations have been linked to ARNSHL and may also cause other conditions, such as Usher syndrome. [5]

[5] OTOF mutations can cause ARNSHL and may also be associated with other symptoms, such as hearing loss in older adults.

Note: The above information is based on the provided text and may not be comprehensive or up-to-date. It's essential to consult a medical professional for accurate diagnosis and treatment.