chromosome 18q deletion syndrome

Chromosome 18q Deletion Syndrome: A Rare Chromosomal Condition

Chromosome 18q deletion syndrome, also known as proximal 18q deletion syndrome, is a rare chromosomal condition that occurs when a piece of the long (q) arm of chromosome 18 is missing. This genetic disorder affects various aspects of an individual's development and health.

Key Features:

• Visual Abnormalities: Some affected individuals may experience visual abnormalities, such as deep-set eyes, microcephaly (small head), and prominent ears [7].
• Hearing Impairment: Hearing impairment is a common feature of this syndrome [5].
• Genital Malformations: Genital malformations and structural heart defects are also possible [1].
• Short Stature and Hypotonia: Affected individuals often experience short stature and hypotonia (low muscle tone) [5].
• Dysmorphic Features: Dysmorphic features, such as a "carp-shaped" mouth, are characteristic of this syndrome [7].
• Intellectual Disability: Intellectual disability is common among individuals with chromosome 18q deletion syndrome [6].

Other Possible Features:

• Multiple congenital anomalies
• Delayed developmental milestones
• Low levels of immunoglobulin

References:

[1] Apr 10, 2009 — Some affected individuals may also have visual abnormalities, hearing impairment, genital malformations, structural heart defects, and/or other ...

[5] by M BUDISTEANU · 2010 · Cited by 12 — The clinical features of this syndrome include short stature, hypotonia, hearing impairment, dysmorphic features, foot deformities, low levels of immunoglobulin ...

[6] Multiple congenital anomalies are possible. · Developmental milestones are always delayed but with considerable variability · Intellectual disability is common ...

[7] In the case of 18q-syndrome, craniofacial abnormalities will most likely include deep-set eyes, a “carp-shaped” mouth, microcephaly (small head), prominent ears ...

Note: The information provided is based on the search results and may not be an exhaustive list of features associated with chromosome 18q deletion syndrome.

Chromosome 18q- Syndrome: A Rare Chromosomal Disorder

Chromosome 18q- syndrome, also known as Chromosome 18, Monosomy 18q, is a rare chromosomal disorder characterized by the deletion of part of the long arm (q) of chromosome 18. This condition can manifest with a wide range of symptoms and severity levels, varying greatly from case to case.

Common Symptoms

The signs and symptoms of proximal 18q deletion syndrome include:

• Short stature [5]
• Mental retardation [5]
• Poor muscle tone (hypotonia) [5]
• Malformations of the hands and feet [5]
• Abnormalities of the skull [5]

Additionally, individuals with this condition may experience: * Developmental delay [6] * Growth hormone deficiency [6] * Hearing loss [6] * Intellectual disability [7]

Increased Risk

This chromosomal disorder increases the risk of birth defects, developmental delay, and learning difficulties [8]. The severity of the condition depends on the size and location of the deletion and which genes are involved.

Variability in Phenotype

The phenotype of proximal 18q deletion syndrome can vary greatly among affected individuals. Some cases may exhibit a more severe presentation, while others may have milder symptoms [9].

References:

• [1] Chromosome 18q- syndrome (also known as Chromosome 18, Monosomy 18q) is a rare chromosomal disorder in which there is deletion of part of the long arm (q) of chromosome 18.
• [2] Proximal chromosome 18q deletion syndrome is a chromosome abnormality that occurs when there is a missing (deleted) copy of genetic material from the part of the long (q) arm near the center of chromosome 18.
• [3] The deletion occurs near the middle of the q arm of the chromosome, typically in an area between regions called 18q11.2 and 18q21.2.
• [4] No direct connection to a single gene in the deletion of chromosome 18 has been made for all the symptoms of 18q-syndrome.
• [5] What Are the Symptoms? · Short stature · Mental retardation · Poor muscle tone (hypotonia) · Malformations of the hands and feet · Abnormalities of the skull and ...
• [6] It is characterized by a wide range of symptoms, including developmental delay, growth hormone deficiency, hearing loss, and intellectual disability.
• [7] Individuals with this condition may experience increased risk of birth defects, developmental delay, and learning difficulties.
• [8] The severity of the condition depends on the size and location of the deletion and which genes are involved.
• [9] The phenotype of proximal 18q deletion syndrome can vary greatly among affected individuals.

Chromosome 18q deletion syndrome can be diagnosed through various genetic tests.

• Fluorescent In Situ Hybridization (FISH) is a commonly used method to diagnose 18q-syndrome [1]. This test helps identify the deletion of part of the long arm (q) of chromosome 18.
• Chromosome Karyotype Analysis and High-Throughput Sequencing are also used to diagnose this condition [4].
• A high resolution SNP or CGH microarray can determine exactly which genes are involved in the deletion, providing important information for diagnosis and treatment [7].

Additionally, a thorough medical evaluation is usually performed after birth to identify any dysmorphic features associated with 18q syndrome [9].

Treatment Options for Chromosome 18q Deletion Syndrome

Chromosome 18q deletion syndrome, also known as distal 18q deletion syndrome, is a rare genetic disorder caused by the deletion of a part of the long arm (q) of chromosome 18. While there is no cure for this condition, various treatment options are available to manage its symptoms and improve quality of life.

Growth Hormone Treatment

Research has shown that growth hormone (rhGH) therapy can be beneficial in treating individuals with chromosome 18q deletion syndrome [2][4]. Long-term rhGH supplementation has been reported to promote significant therapeutic benefits, including improved final body height and weight gain [4].

Supportive Care

In addition to growth hormone treatment, supportive care is essential for managing the symptoms of chromosome 18q deletion syndrome. This may include:

• Weight management: Maintaining a healthy weight through a balanced diet and regular exercise can help alleviate symptoms such as reflux and immunological issues [3].
• Immunology/Rheumatology: Monitoring and managing immunological and rheumatological conditions, such as IgA deficiency, is crucial for individuals with chromosome 18q deletion syndrome [3].
• Genitourinary care: Managing genitourinary symptoms, including reflux, requires regular medical check-ups and appropriate treatment [3].

Surgical Interventions

In some cases, surgical interventions may be necessary to correct craniofacial abnormalities associated with chromosome 18q deletion syndrome [9]. However, this is typically not a primary treatment approach.

It's essential to note that each individual with chromosome 18q deletion syndrome may require a unique treatment plan, taking into account their specific symptoms and medical history. A multidisciplinary team of healthcare professionals should be involved in developing an effective treatment strategy.

References:

[1] Not applicable (no relevant information found)

[2] S Liu · 2021 · Cited by 5 — [Context #2]

[3] Distal 18q- Treatment and Surveillance ; Failure to thrive/growth failure. Weight gain; Linear growth ; Genitourinary. Reflux ; Immunology/Rheumatology. IgA ... [Context #3]

[4] by T Jackowski · 2019 · Cited by 1 — [Context #4]

[5] Not applicable (no relevant information found)

[6] S Liu · 2021 · Cited by 5 — [Context #6]

[7] Not applicable (no relevant information found)

[8] Nov 1, 2018 — Proximal 18q deletion syndrome is a chromosomal condition that occurs when a piece of the long (q) arm of chromosome 18 is missing. [Context #8]

[9] Surgery can correct some of the craniofacial abnormalities often present in 18q-syndrome. Beyond this, treatment of 18q-syndrome is supportive, and can ... [Context #9]

Differential Diagnosis of Chromosome 18q Deletion Syndrome

Chromosome 18q deletion syndrome, also known as distal 18q deletion syndrome, is a rare chromosomal condition that occurs when a piece of the long (q) arm of chromosome 18 is missing. The differential diagnosis for this condition involves considering other genetic and non-genetic conditions that may present with similar symptoms.

Similar Conditions:

• Prader-Willi Syndrome: This condition also presents with short stature, hypotonia, and developmental delay, but it is typically associated with a deletion of the paternal copy of chromosome 15 (q11-q13) [1].
• Angelman Syndrome: Similar to Prader-Willi syndrome, Angelman syndrome is characterized by developmental delay, intellectual disability, and seizures, but it is caused by a deletion or mutation of the UBE3A gene on chromosome 15 [2].
• Wolf-Hirschhorn Syndrome: This condition presents with severe intellectual disability, short stature, and characteristic facial features, but it is caused by a deletion of the short arm of chromosome 4 (p16.3) [3].
• Cri-du-Chat Syndrome: Similar to Wolf-Hirschhorn syndrome, Cri-du-Chat syndrome is characterized by intellectual disability, short stature, and distinctive facial features, but it is caused by a deletion of the short arm of chromosome 5 (p15.2-p13.1) [4].

Key Features:

• Short Stature: Short stature is a common feature in all these conditions, including chromosome 18q deletion syndrome.
• Developmental Delay: Developmental delay and intellectual disability are also shared features among these conditions.
• Hypotonia: Hypotonia (low muscle tone) is another common feature that may be present in some