autosomal recessive nonsyndromic deafness 7

Autosomal Recessive Nonsyndromic Deafness 7 (ARND7) is a form of non-syndromic sensorineural hearing loss caused by mutations in the TMC1 gene on chromosome 9q21 [4]. This condition is characterized by prelingual onset with severe to profound, stable hearing loss [8].

The symptoms of ARND7 typically manifest before speech development (prelingual deafness) and are often associated with autosomal recessive nonsyndromic deafness [9]. The hearing loss in ARND7 is usually bilateral and can range from mild to profound in severity.

ARND7 is a genetic disorder that affects the inner ear, specifically the cochlea, leading to hearing impairment. It 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 [1][6].

It's worth noting that ARND7 is a rare form of hearing loss and more research is needed to fully understand its characteristics and implications.

Autosomal recessive nonsyndromic deafness, also known as GJB2-related hearing loss, can manifest in various ways depending on the severity of the condition. According to recent research [6], the diagnosis should be considered in two scenarios: an abnormal audiogram or a family history of hearing loss.

The clinical spectrum of autosomal recessive nonsyndromic deafness may range from mild symptoms to more severe manifestations, including:

• Mild symptoms: Some individuals with autosomal recessive nonsyndromic deafness may not experience any noticeable symptoms, while others may have a slight reduction in hearing sensitivity [5].
• Vertigo and balance issues: In some cases, the condition can cause vertigo, dizziness, or balance problems due to the impact on the inner ear's vestibular system.
• Hearing loss: The most common symptom of autosomal recessive nonsyndromic deafness is hearing loss, which can range from mild to profound. This can affect one or both ears and may be accompanied by tinnitus (ringing in the ears) [7].

It's essential to note that the severity and progression of symptoms can vary significantly among individuals with autosomal recessive nonsyndromic deafness.

References: [5] MD Venkatesh · 2015 · Cited by 48 [6] Jul 20, 2023 [7] May 15, 2024

Autosomal Recessive Nonsyndromic Deafness 7 (ARNSD7) is a form of non-syndromic sensorineural hearing loss caused by mutations in the TMC1 gene on chromosome 9q21. Diagnostic tests for ARNSD7 are crucial for accurate diagnosis and management.

Available Genetic Tests

According to search results, there are available genetic tests from US labs and around the world that can help diagnose ARNSD7. These tests can identify mutations in the TMC1 gene, which is associated with this condition [6].

Clinical Features and Diagnosis

ARNSD7 is characterized by severe-to-profound autosomal recessive nonsyndromic hearing loss. The diagnosis of ARNSD7 is established in a proband with suggestive findings and confirmed through molecular genetic testing [9]. This test plays a crucial role in identifying the underlying cause of the disease.

Other Diagnostic Tests

While not specifically mentioned for ARNSD7, other diagnostic tests like CT scans can help detect malformations of the inner ear associated with this condition [5].

Genetic Testing and Diagnosis

Molecular genetic testing is essential for diagnosing ARNSD7. This test can identify mutations in the TMC1 gene, which is responsible for this condition. The diagnosis of GJB2-related autosomal recessive nonsyndromic hearing loss (GJB2-AR NSHL) is established in a proband with suggestive findings and confirmed through molecular genetic testing [10].

References

• Search result 4: Available tests. 36 tests are in the database for this condition.
• Search result 9: by RJH Smith · Cited by 241 — Diagnosis/testing.​​ Molecular genetic testing, available in clinical laboratories for many types of syndromic and nonsyndromic deafness, plays a ...
• Search result 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.
• Search result 5: This form

Unfortunately, there is no pharmacological treatment currently available for autosomal recessive nonsyndromic deafness.

However, researchers are exploring gene therapy as a promising approach for treating hereditary deafness. A study published in 2024 reported the safety and efficacy of gene therapy using adeno-associated viruses (AAVs) in treating congenital deafness [8]. Another study demonstrated the potential of gene therapy to restore hearing in individuals with autosomal recessive nonsyndromic deafness [6].

While these findings are promising, it's essential to note that gene therapy is still an emerging field, and more research is needed to fully understand its effectiveness and potential risks. As such, there is no established drug treatment for autosomal recessive nonsyndromic deafness.

References: [8] Jan 24, 2024 — However, no pharmacological treatment is currently available for congenital deafness. In this Article, we report the safety and efficacy of gene ... [6] by H Wang · 2024 · Cited by 11 — Gene therapy is a promising approach for hereditary deafness. We recently showed that unilateral AAV1-hOTOF gene therapy with dual ...

Autosomal recessive nonsyndromic deafness 7 (DFNA7) is a form of progressive sensorineural hearing loss with highly variable age at onset and severity. To determine the differential diagnosis for this condition, it's essential to consider other possible causes of hearing loss that may present similarly.

• Other forms of autosomal dominant deafness: Conditions like DFNA2A, caused by mutations in the KCNQ4 gene, can also lead to progressive sensorineural hearing loss. These conditions often have a similar age at onset and severity as DFNA7 [8].
• Autosomal recessive nonsyndromic deafness: This condition is characterized by congenital or prelingual hearing loss, which may be severe in most cases [9]. The differential diagnosis for autosomal recessive nonsyndromic deafness includes conditions like DFNB1, caused by mutations in the GJB2 gene.
• Sensory neural hearing loss: This type of hearing loss can be caused by various factors, including genetic mutations, infections, or exposure to loud noises. Conditions like otosclerosis or Meniere's disease may also present with similar symptoms [3].
• Other genetic conditions: Certain genetic disorders, such as Usher syndrome or Pendred syndrome, can cause progressive sensorineural hearing loss and should be considered in the differential diagnosis for DFNA7.

It is crucial to note that a comprehensive evaluation by an audiologist or a geneticist may be necessary to determine the underlying cause of hearing loss in individuals suspected of having autosomal recessive nonsyndromic deafness 7.