non-syndromic X-linked intellectual disability 106

Non-syndromic X-linked intellectual disability (NS-XLID) refers to a group of conditions characterized by intellectual disability in males, with no other associated physical or medical symptoms.

• Definition: NS-XLID is a condition where a mutation on the X chromosome leads to intellectual disability in males. The condition is not associated with any other physical or medical symptoms.
• Prevalence: The prevalence of NS-XLID is unknown, as it is a relatively rare condition.
• Inheritance: NS-XLID is inherited in an X-linked recessive pattern, meaning that the mutated gene is located on the X chromosome and only affects males.
• Age of onset: The age of onset for NS-XLID varies, but it typically becomes apparent during childhood or infancy.

There are several types of NS-XLID, each caused by a different mutation on the X chromosome. Some of these include:

• Non-syndromic X-linked intellectual disability 1 (NS-XLID1)
• Non-syndromic X-linked intellectual disability 14 (NS-XLID14)
• Non-syndromic X-linked intellectual disability 106 (NS-XLID106)

Each type of NS-XLID has its own unique characteristics and symptoms. However, in general, all types of NS-XLID are characterized by intellectual disability in males, with no other associated physical or medical symptoms.

References:

• [1] Non-syndromic X-linked intellectual disability 106 is characterized by moderate intellectual disability and impaired speech. It is caused by a mutation in a gene on the X chromosome. (Source: #7)
• [2] NS-XLID is a condition where a mutation on the X chromosome leads to intellectual disability in males, with no other associated physical or medical symptoms. (Source: #6)
• [3] The prevalence of NS-XLID is unknown, as it is a relatively rare condition. (Source: #6)

Signs and Symptoms of Non-Syndromic X-Linked Intellectual Disability

Non-syndromic X-linked intellectual disability (XLID) is characterized by intellectual disability in the absence of other symptoms or signs. The clinical features of XLID include:

• Delayed Development: Affected boys often have delayed development of motor skills such as walking, and their speech may be delayed [1].
• Weak Muscle Tone: Most affected children have weak muscle tone (hypotonia), which delays motor skills such as sitting, standing, and walking [8].
• Intellectual Disability: The primary symptom of XLID is intellectual disability, which can range from mild to severe.
• No Other Symptoms or Signs: Unlike syndromic XLID, non-syndromic XLID does not display other symptoms or signs.

It's worth noting that the prevalence and inheritance pattern of X-linked non-syndromic intellectual disability are unknown [5]. However, it is a rare, hereditary, neurologic disease characterized by early-onset cognitive impairment as a sole disability [6].

References: [1] Context result 2 [8] Context result 8

Non-syndromic X-linked intellectual disability (NS-XLMR) can be challenging to diagnose, but various diagnostic tests are available to help identify the underlying genetic cause.

• Chromosomal Microarray Analysis (CMA): This is a first-line genetic test recommended by medical genetics groups for children with intellectual disabilities. CMA can detect deletions or duplications of genetic material on the X-chromosome, which may be associated with NS-XLMR [5].
• Genetic testing: Specific genetic tests are available to identify mutations in genes known to cause NS-XLMR. These tests can help diagnose the specific type of intellectual disability present and guide treatment.
• Clinical evaluation: A thorough clinical evaluation by a medical genetics specialist is essential to rule out other causes of intellectual disability and to identify any associated physical or behavioral symptoms.

It's worth noting that genetic testing can be complex, and results may not always provide a clear diagnosis. In such cases, further testing or consultation with a genetic counselor may be necessary [9].

References: [5] - Medical genetics groups recommend chromosomal microarray analysis (CMA) as a first-line genetic test to identify genetic mutations in children with intellectual disabilities. [9] - Genetic testing can help diagnose the specific type of intellectual disability present and guide treatment. Early intervention can significantly benefit individuals with NS-XLMR.

Based on the provided context, it appears that there are limited treatment options available for non-syndromic X-linked intellectual disability.

• Currently, there is no specific pharmacologic treatment available for cognitive impairment in individuals with non-syndromic X-linked intellectual disability [9].
• Acamprosate, a drug approved by the FDA for the maintenance of abstinence from alcohol, has been suggested as another potential treatment targeting glutamate/GABA imbalance, but its effectiveness is not well established [3].

It's essential to note that any non-syndromic X-linked intellectual disability should be managed in consultation with a healthcare professional, who can provide personalized guidance and support [7].

Differential Diagnoses for Non-Syndromic X-Linked Intellectual Disability

Non-syndromic X-linked intellectual disability (NS-XLID) is a condition characterized by intellectual disability in the absence of other symptoms or co-morbid features. When diagnosing NS-XLID, it's essential to consider differential diagnoses that may present similar symptoms.

Other Forms of X-Linked Intellectual Disability

• Other forms of X-linked ID should be considered as differential diagnoses for NS-XLID [2].
• These conditions involve similar symptoms or clinical findings and can be ruled out through genetic testing and evaluation [8].

Autism Spectrum Disorder, Borderline Intellectual Functioning, and Child Abuse & Neglect

• Differential diagnosis also includes Autism Spectrum Disorder (ASD), borderline intellectual functioning, and child abuse & neglect, which may present with similar symptoms [4].
• Posttraumatic Stress Disorder (PTSD) is another condition that should be considered in the differential diagnosis of NS-XLID.

Rare Syndromes: Börjeson-Forssman-Lehmann Syndrome, Wilson-Turner Syndrome, and Smith-Fineman-Myers Syndrome

• Rare syndromes such as Börjeson-Forssman-Lehmann syndrome, Wilson-Turner syndrome, and Smith-Fineman-Myers syndrome should also be considered in the differential diagnosis of NS-XLID [5].

Genetic Causes and Associated Pathology

• Non-syndromic ID is characterized by a lack of associated pathology, making genetic causes a crucial aspect of diagnosis.
• Genes linked with non-syndromic ID are being studied to understand the underlying mechanisms and develop targeted therapies.

References:

[1] Kaufman, L. (2010). Non-Syndromic X-Linked Intellectual Disability: A Systematic Review. [2] Kaufman, L. (2010). Non-Syndromic X-Linked Intellectual Disability: A Systematic Review. [3] Barros, II. (2021). Non-syndromic intellectual disability (NS-ID or idiopathic) is a complex neurodevelopmental disorder that represents a global health issue. [4] Moortgat, S. (2018). The association of HUWE1 variants or rearrangements with X-linked intellectual disability (XLID) is now well recognised. [5] Ilyas, M. (2020). Non-syndromic ID is characterized by a lack of associated pathology.