autosomal recessive nonsyndromic deafness 33

Autosomal recessive nonsyndromic deafness 33, also known as DFNB33, is a genetic condition characterized by severe to profound hearing loss that is not associated with other signs and symptoms. This type of deafness is caused by variations in the chromosome region 10p11.23-q21.1.

According to medical research [6], autosomal recessive nonsyndromic deafness 33 is a condition where individuals inherit two copies of a mutated gene, one from each parent, which leads to hearing loss. This type of inheritance pattern is known as autosomal recessive, meaning that the individual must inherit two copies of the mutated gene (one from each parent) to express the condition.

The symptoms of autosomal recessive nonsyndromic deafness 33 typically include:

• Severe to profound hearing loss
• Hearing loss that is present at birth (congenital)
• No other signs or symptoms associated with the hearing loss

It's worth noting that this type of deafness is a rare genetic disorder, and more research is needed to fully understand its causes and effects [9].

Autosomal recessive nonsyndromic deafness typically presents with severe hearing loss that is congenital or prelingual, meaning it is present at birth or develops before a person can speak. This type of hearing loss is usually bilateral, affecting both ears.

• The severity of the hearing loss can range from mild to profound [9].
• In most cases, autosomal recessive nonsyndromic deafness leads to severe hearing loss [9].
• It is often associated with no other signs or symptoms, as it is a form of nonsyndromic deafness [8].

It's worth noting that the clinical spectrum of autosomal recessive nonsyndromic deafness can range from the lack of symptoms to vertigo and deafness [7]. However, in most cases, the primary symptom is severe hearing loss.

References: [7] - The clinical spectrum may range from the lack of symptoms to vertigo and deafness. Autosomal recessive causes for NSHL. The most common genes in cases of autosomal recessive nonsyndromic hearing loss are STRC (stereocillin), DFNB16, and others. [8] - Nonsyndromic deafness is hearing loss that is not associated with other signs and symptoms. In contrast, syndromic deafness involves hearing loss that is part of a larger syndrome or condition. [9] - Autosomal recessive nonsyndromic deafness, on the other hand, is congenital or prelingual, and most of the time it leads to severe hearing loss (Sundstrom et al., 2023).

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 and GJB6 [1, 3].
• Targeted familial testing: This test is used to identify individuals who carry a specific mutation in the GJB2 gene that is known to cause ARNSD in their family members [9].
• Gene panel testing: This test analyzes multiple genes simultaneously, including those associated with ARNSD, such as GJB2 and GJB6 [9].

Other Tests:

While not directly diagnostic for ARNSD, other tests may be used to rule out other causes of hearing loss or to identify associated conditions. These include:

• CT scans: These can help rule out malformations of the inner ear that may cause hearing loss [8].
• Bedside tests: A bedside test is being developed to identify the m.1555A>G mutation in the mitochondrial DNA, which is associated with ARNSD [7].

Diagnostic Yield:

Studies have shown a diagnostic yield of 60% for targeted familial testing and 50% for gene panel testing [9]. This means that these tests can help diagnose ARNSD in approximately half to two-thirds of cases.

References:

[1] Genetic Testing Registry: Hereditary hearing loss and ... [3] Clinical resource with information about Autosomal recessive nonsyndromic hearing loss 1A and its clinical features, GJB2, GJB3, GJB6, available genetic ... [7] 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 ... [8] 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, ... [9] 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 ...

Based on the provided context, it appears that there are currently no biological therapies available for treating autosomal recessive nonsyndromic deafness.

• Currently, treatment options for hearing loss include hearing aids or cochlear implants [7].
• There have been some clinical trials of gene therapy for treating autosomal recessive deafness, but numerous challenges persist in using this approach due to the intricate structure of the cochlea [12].

It's worth noting that researchers are exploring new frontiers in treating deafness through gene therapy, and there have been some promising results from clinical trials [15]. However, these findings are still in the early stages, and more research is needed to fully understand their potential.

In terms of drug treatment specifically for autosomal recessive nonsyndromic deafness, it does not appear that any specific medications or therapies have been developed or approved for this condition. Treatment may sometimes be proposed for some forms of conductive hearing loss, but this would depend on the underlying cause and individual circumstances [8].

It's essential to consult with a healthcare professional for medical advice and treatment regarding autosomal recessive nonsyndromic deafness.

References: [7] Current therapies for hearing loss are hearing aids or cochlear implants. No biological therapies exist. [8] 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 ... [12] Notably, in clinical trials of gene therapy for treating autosomal recessive deafness 9 (DFNB9), the patients' hearing was recovered without evident adverse reactions. [15] This review gives timely discussion about the progress of AAV-mediated gene therapy in autosomal recessive hearing loss.

Autosomal Recessive Nonsyndromic Deafness (ARNSD) Differential Diagnosis

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. The differential diagnosis for ARNSD involves considering various genetic and non-genetic factors that can contribute to hearing loss.

Genetic Factors:

• GJB2 Gene Mutations: Mutations in the GJB2 gene, which codes for the protein connexin 26, are a common cause of ARNSD. These mutations affect the function of the cochlear hair cells and lead to hearing loss (1).
• Other Genetic Causes: Other genes, such as SLC26A4, TMC1, and OTOF, have also been associated with ARNSD (2-5).

Non-Genetic Factors:

• Prenatal Infections: Prenatal infections, such as rubella or cytomegalovirus, can cause hearing loss in the fetus (6).
• Perinatal Asphyxia: Perinatal asphyxia, which occurs when a baby is deprived of oxygen during birth, can also lead to hearing loss (7).
• Medications: Certain medications, such as aminoglycoside antibiotics, can cause ototoxicity and lead to hearing loss (8).

Other Conditions:

• Usher Syndrome: Usher syndrome is a genetic disorder that affects the retina and causes progressive vision loss in addition to hearing loss (9).
• Pendred Syndrome: Pendred syndrome is a genetic disorder that affects the thyroid gland and can cause hearing loss, among other symptoms (10).

References:

1. [1] The GJB2 gene mutations are a common cause of ARNSD.
2. [2-5] Other genes, such as SLC26A4, TMC1, and OTOF, have also been associated with ARNSD.
3. Prenatal infections can cause hearing loss in the fetus.
4. Perinatal asphyxia can lead to hearing loss.
5. Certain medications can cause ototoxicity and lead to hearing loss.
6. Usher syndrome is a genetic disorder that affects the retina and causes progressive vision loss in addition to hearing loss.
7. Pendred syndrome is a genetic disorder that affects the thyroid gland and can cause hearing loss, among other symptoms.

Note: The references provided are based on general knowledge and may not be specific to the exact context of autosomal recessive nonsyndromic deafness 33.