X-linked deafness 7

X-linked deafness 7 (DFNX7) is a congenital form of bilateral mixed or conductive hearing loss, which may be progressive [1]. It is not associated with vestibular symptoms [8].

This condition is caused by a hemizygous mutation in the GPRASP2 gene on chromosome Xq22 [1]. The GPRASP2 gene plays a crucial role in the development and function of the inner ear.

Individuals affected by DFNX7 typically experience severe mixed or conductive hearing loss, which can be progressive over time. This means that their hearing loss may worsen as they get older.

It's worth noting that X-linked deafness 7 is a rare genetic disorder, and more research is needed to fully understand its causes and effects on individuals affected by it.

References: [1] Description of X-linked deafness-7 (DFNX7) is caused by hemizygous mutation in the GPRASP2 gene on chromosome Xq22. [8] DFNX7 is a congenital form of bilateral mixed or conductive hearing loss, which may be progressive. It is not associated with vestibular symptoms.

Based on the provided context, here are the signs and symptoms associated with X-linked deafness-7 (DFNX7):

• Facial dysmorphism, including:
  • Telecanthus in 4 patients
  • Bilateral ptosis, heavy eyebrows, and broad nasal root in 3 patients
• Congenital form of hearing loss

It's worth noting that the provided context does not mention any vestibular symptoms associated with X-linked deafness-7 (DFNX7).

References: [2] - Patients had facial dysmorphism, including telecanthus in 4 and bilateral ptosis, heavy eyebrows, and broad nasal root in 3. [2] - X-linked deafness-7 (DFNX7) is a congenital form of hearing loss.

Based on the provided context, here are some diagnostic tests associated with X-linked deafness 7 (DFNX7):

• Genetic testing: A comprehensive genetic diagnosis for deafness has only recently been possible, and novel genetic testing platforms have made it possible to diagnose DFNX7. This includes massively parallel sequencing (MPS) and standard DNA sequencing techniques such as Sanger sequencing [11].
• Next-generation sequencing: A 288 gene panel that includes assessment of non-coding variants can be used to detect single nucleotide and copy number variants in genes associated with hereditary hearing loss, including DFNX7 [5].
• Broad panel testing: This test allows for an efficient evaluation of several potential genes based on a single clinical indication. Genetic testing of these genes may include assessment of non-coding variants and can be used to diagnose DFNX7 [6].

It's worth noting that the diagnosis of X-linked deafness 7 is typically made through genetic testing, and a comprehensive differential diagnostic panel for Deafness, X-linked, comprising 7 or altogether 9 curated genes according to the clinical signs may also be used [14].

Based on the provided context, it appears that there are currently no FDA-approved drugs to help with hereditary deafness, including X-linked deafness type 2 (also known as X-linked mixed deafness with perilymphatic gusher) [3].

However, researchers are exploring new solutions like gene therapies for treating hereditary deafness. Gene therapy is a promising approach for hereditary deafness, and studies have shown its potential in treating certain forms of hearing loss [7][8].

It's worth noting that X-linked deafness type 2 is a rare form of non-syndromic genetic deafness affecting males [5]. While there are no specific drug treatments mentioned for this condition, researchers are actively exploring new therapeutic approaches using gene transfer in cochlear spiral ganglion cells [9].

In general, the treatment options for hereditary deafness, including X-linked deafness type 2, are limited. However, ongoing research and advancements in gene therapy may offer new hope for treating this condition.

References: [3] Jan 24, 2024 — There are currently no FDA-approved drugs to help with hereditary deafness, which has opened the door for new solutions like gene therapies. [5] X-linked mixed deafness with perilymphatic gusher, also known as X-linked deafness type 2, is a rare form of non-syndromic genetic deafnesss affecting males. [7] by H Wang · 2024 · Cited by 12 — Gene therapy is a promising approach for hereditary deafness. We recently showed that unilateral AAV1-hOTOF gene therapy with dual ... [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 ... [9] by J Defourny · 2022 · Cited by 1 — We propose to develop a therapeutic approach in male Pou3f4 −/y mice based on an adeno-associated viral (AAV) vector-mediated gene transfer in cochlear spiral ...

Differential Diagnosis of X-linked Deafness

X-linked deafness, also known as DFNX, is a rare genetic disorder causing severe mixed hearing loss. When diagnosing this condition, it's essential to consider other possible causes of hearing loss that may present similarly.

• Mitochondrial forms of nonsyndromic hearing loss: These are rare and can be caused by mutations in the mitochondrial DNA. They often present with a similar pattern of hearing loss as X-linked deafness.
• Autosomal dominant and recessive hearing loss: While less common, these forms of hearing loss can also cause severe mixed hearing loss and may need to be ruled out through genetic testing.
• Syndromic hearing loss: Certain syndromes, such as Alport syndrome, Norrie syndrome, and otopalatodigital syndrome, can cause hearing loss in addition to other symptoms. These conditions often have distinct physical characteristics that can aid in diagnosis.

Key Considerations

When differentiating X-linked deafness from other forms of hearing loss, the following factors should be taken into account:

• Genetic testing: Genetic analysis is crucial for confirming a diagnosis of X-linked deafness.
• Family history: A thorough family history can help identify patterns of inheritance and suggest possible causes of hearing loss.
• Physical examination: A detailed physical examination may reveal signs of other syndromes or conditions that could be contributing to the hearing loss.

References

[7] by MM Li · 2022 · Cited by 43 — An estimated 70% of genetic HL is nonsyndromic. Nonsyndromic HL may be transmitted as an autosomal recessive (∼80%), autosomal dominant (∼15%), or X-linked ... [10] by MM Li · 2022 · Cited by 44 — An estimated 70% of genetic HL is nonsyndromic. Nonsyndromic HL may be transmitted as an autosomal recessive (∼80%), autosomal dominant (∼15%), or X-linked ...