autosomal recessive nonsyndromic deafness 62

Autosomal Recessive Nonsyndromic Deafness 62 (DFNA2) is a genetic condition characterized by non-syndromic sensorineural hearing loss. This type of hearing loss is caused by variations in the chromosome region 12p13.2-p11.23.

Causes and Genetics

• DFNA2 is an autosomal recessive trait, meaning that it is inherited from both parents who are carriers of the mutated gene.
• The condition is caused by mutations in a specific gene on chromosome 12, which affects the development or function of the inner ear.
• The genetic basis of DFNA2 involves variation in the chromosome region 12p13.2-p11.23.

Prevalence and Inheritance

• More than 50% of prelingual hearing loss is genetic in origin [3].
• Up to 93% of monogenic autosomal recessive traits are responsible for prelingual hearing loss [3].
• DFNA2 is a rare form of non-syndromic deafness, but its exact prevalence is unknown.

References

• [1] A form of sensorineural deafness with either congenital onset or infantile onset, i.e., before the acquisition of speech.
• [4] Deafness, autosomal recessive 62 is a genetic condition characterized by nonsyndromic deafness caused by variations in the chromosome region 12p13.2-p11.23.
• [7] Disease Ontology Definition: An autosomal recessive nonsyndromic deafness that has material basis in variation in the chromosome region 12p13.2-p11.23.
• [9] An autosomal recessive nonsyndromic deafness that has material basis in variation in the chromosome region 12p13.2-p11.23.

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.

Common Signs and Symptoms:

• Prelingual onset: Hearing loss typically begins before language development, often at birth or shortly after.
• Severe to profound hearing loss: The majority of individuals with ARNSD experience severe to profound hearing loss affecting all frequencies.
• Stable hearing loss: The hearing loss is usually stable and does not progress over time.

Other Key Points:

• ARNSD is the most common form of nonsyndromic deafness, accounting for 75-80% of cases.
• It is often inherited in an autosomal recessive pattern, meaning that a person must inherit two copies of the mutated gene to express the condition.
• The hearing loss can be congenital or prelingual, meaning it is present at birth or develops shortly after.

References:

• [1] - Autosomal recessive nonsyndromic deafness typically presents as a congenital or prelingual, severe to profound deafness affecting all frequencies while [7].
• [6] - An autosomal recessive nonsyndromic deafness that is characterized by prelingual onset with usually severe to profound, stable hearing loss and has material basis in mutation in [5].

Autosomal recessive nonsyndromic deafness (ARNSD) is a form 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:

• Genetic testing for the GJB2 and GJB6 genes can be used to diagnose ARNSD. These genes are commonly associated with this form of hearing loss [1][3].
• A bedside test is in development that can be used to identify the m.1555A>G mutation in the mitochondrial DNA, which is also implicated in autosomal dominant hearing loss [7].
• Targeted familial testing and gene panel testing have been shown to have a diagnostic yield of 60% and 50%, respectively [9].

Clinical Features:

• ARNSD is often associated with malformations of the inner ear that can be detected by CT scan [8].
• In rare cases, thyroid gland disease may also be present in individuals with ARNSD.

It's worth noting that genetic testing has not been proposed as a primary screen for hearing loss, and genes associated with hereditary hearing loss may be associated with other conditions as well [4].

References: [1] - Context 2 [3] - Context 2 [7] - Context 7 [8] - Context 8 [9] - Context 9

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). Hereditary hearing loss: A review of current clinical treatments and emerging gene therapy approaches. [7] Brotto, D. (2024). Gene therapy for hereditary deafness: A new frontier in treatment options. [9] Disease Overview. Any autosomal recessive nonsyndromic deafness in ...

Differential Diagnosis of Autosomal Recessive Nonsyndromic Deafness

Autosomal recessive nonsyndromic deafness is a type of hearing loss that can be challenging to diagnose, as it does not present with any specific symptoms or syndromes. However, there are several genes and conditions that can be associated with this type of hearing loss, making differential diagnosis crucial.

Associated Genes:

• More than 70 genes have been associated with autosomal recessive nonsyndromic deafness [3].
• GJB2-related autosomal recessive nonsyndromic hearing loss (GJB2-AR NSHL) is the most common genetic cause of congenital severe-to-profound non-progressive sensorineural hearing loss in many world populations [10].

Other Conditions:

• Autosomal dominant loci can also cause postlingual hearing impairment, with some exceptions such as DFNA3, DFNA8, DFNA12, and DFNA19 [7].
• X-linked recessive deafness is a rare condition that affects males more frequently than females [6].

Diagnostic Considerations:

When diagnosing autosomal recessive nonsyndromic deafness, it is essential to consider the following factors:

• Family history of hearing loss
• Age of onset and progression of hearing loss
• Presence of other symptoms or syndromes
• Genetic testing for associated genes

By considering these factors and conducting thorough genetic testing, healthcare providers can accurately diagnose autosomal recessive nonsyndromic deafness and provide appropriate treatment and management.

References:

[3] Jul 20, 2023 — Differential Diagnosis. As of this writing, more than 70 genes have been associated with autosomal recessive nonsyndromic hearing loss. [6] by RJH Smith · Cited by 240 — Hereditary hearing loss can be inherited in an autosomal dominant, autosomal recessive, or X-linked recessive manner, as well as by ... [7] Oct 23, 2016 — Most autosomal dominant loci cause postlingual hearing impairment, with some exceptions such as DFNA3, DFNA8, DFNA12, and DFNA19. [10] GJB2-related autosomal recessive nonsyndromic hearing loss (GJB2-AR NSHL) is the most common genetic cause of congenital severe-to-profound non-progressive sensorineural hearing loss in many world populations.