autosomal dominant nonsyndromic deafness 3A

Autosomal dominant nonsyndromic deafness 3A (DFNA3A) is a genetic condition characterized by prelingual, high-frequency hearing loss [4][6]. This means that the hearing loss typically occurs before language development and affects the higher frequency ranges of sound [7].

The condition is caused by a mutation in the GJB2 gene, which codes for a protein called connexin 26 that plays a crucial role in the functioning of the inner ear's sensory cells [5][8]. This mutation leads to progressive high-frequency sensorineural hearing loss, ranging from mild to profound [1][3].

The inheritance pattern of DFNA3A is autosomal dominant, meaning that a single copy of the mutated gene is sufficient to cause the condition. This means that if one parent has the condition, each child has a 50% chance of inheriting it [2][9].

Autosomal dominant nonsyndromic deafness 3A (DFNA3) is a genetic hearing loss condition that affects the high-frequency sensorineural hearing impairment. The signs and symptoms of this condition are as follows:

• Pre- or postlingual hearing impairment: Individuals with DFNA3 may experience hearing loss either before or after language development.
• Mild-to-profound progressive high-frequency sensorineural hearing impairment: The hearing loss in DFNA3 typically affects the high frequencies, and can range from mild to profound in severity. It is also characterized by a gradual progression over time.
• Sensorineural hearing impairment: This type of hearing loss occurs when there is damage to the inner ear or the auditory nerve.

According to [11], individuals with DFNA3 may experience symptoms such as:

• Hearing loss that starts at any age, from birth to adulthood
• Gradual worsening of hearing over time
• Difficulty understanding high-pitched sounds or voices
• Needing amplification (e.g., hearing aids) to compensate for the hearing loss

It's essential to note that DFNA3 is a genetic condition, and its symptoms can vary in severity and progression from person to person. If you suspect you or someone else may have this condition, it's crucial to consult with an audiologist or a healthcare professional for proper evaluation and guidance.

References: [11] National Center for Advancing Translational Sciences; ... Nonsyndromic hearing loss and deafness, DFNA3 is characterized by pre- or postlingual, mild-to-profound progressive high-frequency sensorineural hearing impairment. ... When Do Symptoms of Deafness ...

Autosomal dominant nonsyndromic deafness 3A (ADND3A) is a form of hearing loss that is caused by mutations in the GJB2 gene. Diagnostic tests for ADND3A are available to identify the genetic mutation responsible for the condition.

Available Genetic Tests

According to search result [1], clinical genetic tests are available from US-based companies, including PreventionGenetics, part of Exact Sciences, which offers testing for conditions such as autosomal dominant nonsyndromic deafness 3A. These tests can help identify the GJB2 gene mutation responsible for ADND3A.

Molecular Genetic Testing

Search result [7] and [8] mention that molecular genetic testing is possible for many types of syndromic and nonsyndromic deafness, including ADND3A. This type of testing plays a prominent role in diagnosis and genetic counseling.

Supplementary Test Information

For Hereditary Hearing Loss - GJB2 and GJB6 Testing, supplementary test information is available, which includes test interpretation and additional tests to consider (search result [6]).

Ideal for Patients with Clinical Suspicion

Search result [9] states that molecular genetic testing is ideal for patients with a clinical suspicion of syndromic or non-syndromic genetic hearing loss. This includes mitochondrial genome analysis.

GJB2 Gene Mutation

ADND3A is caused by mutations in the GJB2 gene on chromosome 13q12 (search result [10]). Diagnostic tests can help identify this specific mutation, which is responsible for the condition.

In summary, diagnostic tests for autosomal dominant nonsyndromic deafness 3A include:

• Clinical genetic tests from US-based companies
• Molecular genetic testing to identify GJB2 gene mutations
• Supplementary test information for Hereditary Hearing Loss - GJB2 and GJB6 Testing
• Mitochondrial genome analysis

These tests can help diagnose ADND3A and provide valuable information for patients, families, and healthcare providers.

Based on the provided context, it appears that there are some experimental studies and gene therapy strategies being explored for treating autosomal dominant nonsyndromic deafness 3A.

• Experimental studies have demonstrated improvements in hearing following a single local injection of adeno-associated virus-derived vectors carrying an ATOH1 gene [9]. This suggests that gene therapy may be a potential treatment option for this condition.
• Gene replacement,

Autosomal dominant nonsyndromic deafness 3A (DFNA3) is a genetic hearing loss condition characterized by pre- or postlingual, mild-to-profound progressive high-frequency sensorineural hearing loss. When considering the differential diagnosis of DFNA3, it's essential to rule out other conditions that may present with similar symptoms.

• Other forms of autosomal dominant nonsyndromic deafness: Conditions like DFNA1 and DFNA2 should be considered in the differential diagnosis, as they also exhibit autosomal dominant inheritance patterns. However, these conditions typically have distinct audiometric profiles and genetic causes [5].
• Autosomal recessive nonsyndromic deafness: This condition often presents with prelingual deafness and may be caused by mutations in genes such as GJB2 or SLC26A4. While the inheritance pattern is different, the symptoms can be similar to those of DFNA3 [6].
• X-linked recessive nonsyndromic deafness: This condition typically affects males and presents with prelingual deafness. However, the genetic cause and audiometric profile may differ from those of DFNA3 [7].

To accurately diagnose DFNA3, a comprehensive evaluation is necessary, including:

• Audiological assessment: A thorough hearing test to determine the extent and progression of hearing loss.
• Genetic testing: Analysis of the GJB2 gene to confirm the presence of mutations associated with DFNA3.
• Family history: Reviewing the patient's family history to identify any patterns of inheritance or other affected relatives.

By considering these factors, healthcare providers can accurately diagnose autosomal dominant nonsyndromic deafness 3A and develop an effective treatment plan for affected individuals [8].

References: [5] - MD Venkatesh · 2015 · Cited by 48 [6] - Autosomal recessive nonsyndromic deafness was noted to frequently have manifestation before speech development (prelingual deafness). A major gene to be ... [7] - 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 ... [8] - by H Azaiez · 2014 · Cited by 114 — In a family segregating progressive autosomal-dominant nonsyndromic hearing loss (NSHL), we used OtoSCOPE® to exclude mutations in known ...