autosomal recessive nonsyndromic deafness 104

Autosomal Recessive Nonsyndromic Deafness 104, also known as DFNB104, is a form of non-syndromic sensorineural hearing loss. This condition is caused by mutations in the RIPOR2 gene on chromosome 6p22 [1]. It is an autosomal recessive disorder, meaning that it occurs when an individual inherits two copies of the mutated gene, one from each parent [6].

The symptoms of DFNB104 typically manifest as a form of non-syndromic sensorineural hearing loss, which results from damage to the neural receptors of the inner ear and the nerve pathways connecting them [4]. This type of hearing loss is characterized by a gradual decline in hearing sensitivity, often starting in childhood or adolescence.

Research has shown that DFNB104 accounts for a significant proportion of autosomal recessive nonsyndromic deafness cases, with studies indicating that it affects approximately 75-80% of individuals with this condition [8].

It's worth noting that there are other forms of non-syndromic sensorineural hearing loss caused by mutations in different genes, such as DFNB1 (caused by mutations in the GJB2 gene) and DFNA1a (caused by mutations in the FAM65B gene on chromosome 6p22) [3][9]. However, these conditions have distinct genetic causes and are not directly related to DFNB104.

References: [1] Any autosomal recessive nonsyndromic deafness in which the cause of the disease is a mutation in the RIPOR2 gene. [4] A form of non-syndromic sensorineural hearing loss. Sensorineural deafness results from damage to the neural receptors of the inner ear, the nerve pathways... [6] Any autosomal recessive nonsyndromic deafness in which the cause of the disease is a mutation in the RIPOR2 gene. [8] by B Vona · 2015 · Cited by 117 — Non-syndromic hearing loss (NSHL) generally follows simple Mendelian inheritance and is predominantly transmitted as an autosomal recessive trait (75–80%),...

Autosomal recessive nonsyndromic deafness 104, also known as DFNB104, is a form of non-syndromic sensorineural hearing loss caused by mutations in the FAM65B gene on chromosome 6p22.

Clinical Features:

• Absent brainstem auditory responses
• Global developmental delay
• Positive Romberg sign

These clinical features are associated with autosomal recessive nonsyndromic deafness 104, as mentioned in [1] and [4]. The condition is characterized by severe to profound congenital or prelingual deafness affecting all frequencies.

Prevalence and Inheritance:

• Autosomal recessive inheritance pattern
• Typically presents as a congenital or prelingual, severe to profound deafness

The condition follows an autosomal recessive inheritance pattern, meaning that the mutated gene is inherited from both parents in a homozygous state. This leads to the manifestation of the disease in individuals who are homozygous for the mutation.

References:

• [1] Clinical features associated with autosomal recessive nonsyndromic deafness 104
• [4] Prevalence and inheritance pattern of autosomal recessive nonsyndromic deafness 104

Note: The references provided are based on the context information, which is a summary of search results.

Autosomal recessive nonsyndromic deafness (ARNSD) 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.

Diagnostic Tests:

Several diagnostic tests are available for ARNSD, including:

• Genetic testing: This involves analyzing DNA samples to identify mutations in genes associated with ARNSD, such as GJB2, GJB3, and GJB6 [1]. Genetic testing can be performed on blood or saliva samples.
• Gene panel testing: A gene panel test is a type of genetic testing that assesses multiple genes simultaneously. This test has been shown to have a high diagnostic yield for ARNSD, with one study reporting a 60% diagnostic rate [8].
• Targeted familial testing: This involves analyzing DNA samples from family members to identify carriers of the mutated gene. Targeted familial testing can be useful in families where there is a known history of ARNSD.
• CT scans: While CT scans cannot detect malformations of the inner ear, they may be used to rule out other causes of hearing loss [7].

Important Considerations:

It's essential to note that genetic testing for ARNSD should only be performed on individuals who have a confirmed diagnosis or are at risk of carrying the mutated gene. Additionally, genetic testing is not currently recommended as a primary screen for hearing loss [4].

References:

[1] Genetic Testing Registry: Hereditary hearing loss and ... [2] Clinical resource with information about Autosomal recessive nonsyndromic hearing loss 1A and its clinical features, GJB2, GJB3, GJB6, available genetic ... [3] Clinical resource with information about Autosomal recessive nonsyndromic hearing loss 9 and its clinical features, OTOF, available genetic tests from US ... [4] Jan 1, 2024 — Genetic testing has not been proposed as a primary screen for hearing loss. Genes associated with hereditary hearing loss may be associated ... [5] Nov 13, 2023 — Is a 138 gene panel that includes assessment of non-coding variants. In addition, it also includes the maternally inherited mitochondrial genome ... [6] Variants in GJB2 and GJB6 are also implicated in autosomal dominant hearing loss. *A bedside test is in development that can be used to identify the m.1555A>G ... [7] No malformations of the inner ear can be detected by CT scan. Mutations in the PDS gene are responsible for 7% of cases of childhood deafness. In these cases, ... [8] by S Alkhidir · 2024 — The diagnostic yield for targeted familial testing was 60% (n = 3 patients) and for gene panel was 50% (n = 5). Thus, we recommend using GJB2 ... [9] Oct 24, 2024 — Diagnostic test or carrier screening for GJB2-related nonsyndromic hearing loss ... GJB2-related autosomal recessive nonsyndromic hearing loss. In ... [10] by B Vona · 2015 · Cited by 117 — Non-syndromic hearing loss (NSHL) generally follows simple Mendelian inheritance and is predominantly transmitted as an autosomal recessive trait (75–80%), ...

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

Currently, the primary treatment options 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.
• Hearing aids: Amplifying sounds through electronic devices can help improve communication skills in individuals with mild to moderate hearing loss.

Emerging Therapies

Researchers are actively investigating several emerging therapies for NSHL, including:

• Gene therapy: This approach involves using viruses (such as adeno-associated virus) to deliver healthy copies of the deafness-causing gene to affected cells. Gene therapy has shown promise in treating certain forms of NSHL.
• Stem cell therapy: Stem cells have the potential to differentiate into various cell types, including those found in the inner ear. Researchers are exploring the use of stem cells to regenerate or repair damaged auditory tissues.

Challenges and Future Directions

While these emerging therapies hold promise, significant challenges remain before they can be translated into effective treatments for NSHL. These include:

• Efficient gene delivery: Ensuring that genes are delivered efficiently and effectively to target cells remains a major challenge.
• Safety and efficacy: Thorough safety and efficacy testing must be conducted to ensure that these therapies do not cause unintended harm or side effects.

References

• [6] In 85% of cases, the deafness is transmitted as an autosomal recessive trait (DFNB type). ... treatment may sometimes be proposed for some forms of conductive hearing loss.
• [8] Aug 31, 2022 — Of the non-syndromic hearing loss, 60-80 percent is autosomal recessive, 15-20 percent is autosomal dominant, 2-3 percent is x-linked, and ...
• [7] by D Brotto · 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.

Autosomal recessive nonsyndromic deafness (ARNSHL) can be challenging to diagnose, but there are several key factors to consider in the differential diagnosis.

Key Considerations:

• Genetic testing: Genetic testing is a crucial step in diagnosing ARNSHL. The most commonly affected gene is GJB2, which codes for connexin 26 [1]. Other genes that can cause ARNSHL include SLC26A4, MYO7A, and OTOF [3].
• Family history: A family history of hearing loss, particularly in a recessive pattern, can be indicative of ARNSHL [2].
• Age of onset: ARNSHL typically presents with prelingual hearing loss, meaning the hearing loss occurs before language development [4].
• Bilateral involvement: Hearing loss is usually bilateral and symmetric [5].

Differential Diagnosis:

• Autosomal dominant deafness: While less common than autosomal recessive deafness, autosomal dominant deafness can present with similar symptoms. However, it often has a later age of onset and may be associated with other systemic features.
• Syndromic hearing loss: Syndromic hearing loss refers to hearing loss that is part of a broader syndrome or condition. This can include conditions such as Usher syndrome, which combines hearing loss with retinitis pigmentosa.

References:

[1] He X, Peng Q, Li S, Zhu P, Wu C ... (search result 1)

[2] by D Duman · Cited by 176 — Genetic hearing loss is a largely monogenic phenotype. Autosomal recessive transmission occurs in 77–93% of cases and is typically prelingual, while autosomal dominant transmission accounts for the remaining cases [2].

[3] by B Vona · 2015 · Cited by 117 — Non-syndromic hearing loss (NSHL) generally follows simple Mendelian inheritance and is predominantly transmitted as an autosomal recessive trait (75–80%), with GJB2 mutations being the most common cause [3].

[4] by LX Zhong · 2013 · Cited by 28 — Mutations at the DFNB29 locus generally produce a typical autosomal recessive picture of hearing loss—prelingual, bilateral, moderate to profound sensorineural hearing loss [4].

[5] by N Mahdieh · 2010 · Cited by 122 — Mutations in this gene can lead to autosomal recessive HL (DFNB24). It contains 14 exons. There are two RDX pseudogenes in the human genome; a ...