autosomal recessive nonsyndromic deafness 88

Autosomal Recessive Nonsyndromic Deafness 88 (DFNB88) is a form of non-syndromic deafness characterized by severe to profound mixed conductive and sensorineural hearing loss. This type of hearing impairment typically manifests before speech development, also known as prelingual deafness.

The cause of DFNB88 is attributed to mutations in the ELMOD3 gene located on chromosome 2p11 [1][6][7][10]. The ELMOD3 gene plays a crucial role in maintaining the integrity and function of the inner ear, and mutations in this gene can lead to hearing loss.

DFNB88 is inherited in an autosomal recessive pattern, meaning that an individual must inherit two copies of the mutated gene (one from each parent) to express the condition [8]. This type of inheritance means that carriers of the mutated gene are typically asymptomatic but can pass the mutation on to their offspring.

The symptoms of DFNB88 include:

• Severe to profound mixed conductive and sensorineural hearing loss
• Prelingual onset, meaning hearing loss occurs before speech development
• Non-syndromic deafness, meaning the condition is not associated with any other physical or developmental abnormalities

It's essential to note that DFNB88 is a rare form of hearing impairment, and more research is needed to fully understand its characteristics and implications.

References:

[1] Duman et al. (Summary of reported mutations in 42 genes in families with autosomal recessive nonsyndromic deafness) [2] [6] Definition: An autosomal recessive nonsyndromic deafness that has_material_basis_in mutation in the ELMOD3 gene on chromosome 2p11. [6] [7] Disease Ontology Definition:An autosomal recessive nonsyndromic deafness that has_material_basis_in mutation in the ELMOD3 gene on chromosome 2p11. [7] [8] Autosomal recessive nonsyndromic deafness was noted to frequently have manifestation before speech development (prelingual deafness). A major gene to be associated with this condition is the ELMOD3 gene. [8] [10] Disease Ontology Definition:An autosomal recessive nonsyndromic deafness that has_material_basis_in mutation in the ELMOD3 gene on chromosome 2p11. [10]

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 develop the condition.

Prelingual Onset: ARNSHL typically presents as a congenital or prelingual hearing loss, meaning that it occurs before a person can speak or learn language. This type of hearing loss is usually severe to profound and affects all frequencies.

• Severe to Profound Hearing Loss: Individuals with ARNSHL often experience stable hearing loss that is severe to profound in severity.
• Prelingual Onset: The onset of ARNSHL is typically prelingual, meaning it occurs before a person can speak or learn language.

According to [6], this type of deafness has material basis in mutation in the gene responsible for ARNSHL.

Autosomal recessive nonsyndromic deafness (ARNSHL) is a genetic disorder that affects hearing, and diagnostic tests play a crucial role in identifying the condition.

Molecular Genetic Testing The primary diagnostic test for ARNSHL is molecular genetic testing. This involves analyzing DNA samples from affected individuals to identify mutations in genes associated with the condition [9]. The most common gene associated with ARNSHL is GJB2, and mutations in this gene account for approximately half of all severe-to-profound cases [2].

Other Diagnostic Tests In addition to molecular genetic testing, other diagnostic tests may be used to support a diagnosis of ARNSHL. These include:

• Audiometric testing: This involves measuring hearing thresholds using audiometry equipment.
• Physical examination: A thorough physical examination can help identify any associated malformations or abnormalities.
• Family history: A detailed family history is essential in identifying patterns of inheritance and potential carriers.

Genetic Testing for Carriers For families with a history of ARNSHL, genetic testing can be used to identify carriers. This involves analyzing DNA samples from parents or other relatives to determine if they carry the mutation [7].

Prenatal Diagnosis In some cases, prenatal diagnosis may be possible using cell-free DNA (cfDNA) screening methods [14]. However, this is not a primary diagnostic test for ARNSHL.

It's essential to note that genetic testing has not been proposed as a primary screen for hearing loss. Genes associated with hereditary hearing loss may also be associated with other conditions, and a comprehensive evaluation by an otolaryngologist or geneticist is necessary to establish a diagnosis [4].

References:

[2] 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 ...

[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 ...

[7] Autosomal recessive non-syndromic hearing loss​​ Parental carrier testing should be offered, where relevant, to confirm that parents are carriers and that the ...

[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 ...

[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.

Autosomal recessive nonsyndromic deafness, also known as DFNB type, accounts for approximately 85% of cases of non-syndromic hearing loss. As of my knowledge cutoff in 2024, there is no specific drug treatment available for autosomal recessive nonsyndromic deafness.

However, researchers are exploring various gene therapy approaches to treat this condition. For example, a study published in 2023 demonstrated the effectiveness of AAV1-hOTOF gene therapy in treating hereditary deafness [5]. Another study from 2024 discussed the potential of gene therapy based on adeno-associated viruses (AAVs) for the treatment of hereditary deafness [7].

Currently, the primary treatments for autosomal recessive nonsyndromic deafness are cochlear implants or hearing aids. These devices can significantly improve communication and quality of life for individuals with this condition.

It's essential to consult with a healthcare professional for personalized medical advice and treatment. They can help determine the best course of action based on individual circumstances [9].

References: [5] Jiang, L. (2023). Gene therapy for hereditary hearing loss: A review. [7] Brotto, D. (2024). Gene therapy for hereditary deafness using adeno-associated viruses. [9] Disease Overview. Any autosomal recessive nonsyndromic deafness in ...

Autosomal recessive nonsyndromic deafness (ARNSHL) can be challenging to diagnose, as it often presents with similar symptoms to other forms of hearing loss. However, there are some key factors that can help in making a differential diagnosis.

Key characteristics of ARNSHL:

• Congenital or prelingual deafness: Most cases of ARNSHL present with severe-to-profound bilateral deafness from birth or before speech development (prelingual deafness) [4].
• Autosomal recessive inheritance pattern: ARNSHL is inherited in an autosomal recessive manner, meaning that a person must inherit two copies of the mutated gene (one from each parent) to express the condition [2].
• Bilateral involvement: The hearing loss in ARNSHL is typically bilateral, affecting both ears equally.

Differential diagnosis:

When considering a differential diagnosis for ARNSHL, the following conditions should be ruled out:

• Autosomal dominant nonsyndromic deafness (ADNSHL): This condition presents with postlingual hearing impairment and can be inherited in an autosomal dominant manner [8].
• X-linked recessive nonsyndromic deafness: This condition is less common and typically affects males, as the mutated gene is located on the X chromosome [6].
• Syndromic hearing loss: Certain genetic syndromes, such as Usher syndrome or Pendred syndrome, can also present with hearing loss. These conditions often have additional clinical features that distinguish them from ARNSHL.

Diagnostic approaches:

To diagnose ARNSHL, a combination of the following approaches may be used:

• Genetic testing: Genetic testing can identify mutations in genes associated with ARNSHL, such as GJB2 or OTOF [3].
• Family history: A thorough family history is essential to determine if there is a pattern of inheritance consistent with an autosomal recessive condition.
• Audiological evaluation: Comprehensive audiological evaluations, including hearing thresholds and speech audiometry, can help confirm the diagnosis.

In conclusion, while ARNSHL can be challenging to diagnose, a combination of clinical features, family history, and genetic testing can help make a differential diagnosis.