Chromosome 5q deletion syndrome

Chromosome 5q deletion syndrome is a rare genetic disorder characterized by the deletion of part of the long arm (q) of chromosome 5. This condition is associated with a variety of clinical manifestations, including but not limited to, physical abnormalities, developmental delays, and an increased risk of certain blood disorders. The syndrome is particularly noted for its association with a specific form of bone marrow failure known as myelodysplastic syndrome (MDS), particularly the subtype known as 5q- syndrome, which is a more specific form of the condition affecting adults.

Causes

The primary cause of Chromosome 5q deletion syndrome is a deletion of genetic material on the long arm of chromosome 5. This deletion can vary in size and location on the chromosome, which contributes to the variability in symptoms and severity observed among affected individuals. The exact reason why this deletion occurs is not fully understood, but it is believed to involve a combination of genetic and environmental factors.

Symptoms

Symptoms of Chromosome 5q deletion syndrome can vary widely among individuals but commonly include:

• Anemia - A deficiency in the number or quality of red blood cells.
• Thrombocytopenia - A low platelet count, which can lead to increased bleeding and bruising.
• Developmental delay - Delays in reaching milestones in physical, social, and intellectual development.
• Distinctive facial features - Such as a small head size (microcephaly), wide-set eyes, and a high nasal bridge.
• Skeletal abnormalities - Including short stature and abnormalities in the hands and feet.

Diagnosis

Diagnosis of Chromosome 5q deletion syndrome typically involves a combination of clinical evaluation and genetic testing. Cytogenetic analysis, such as karyotyping, can identify the deletion on chromosome 5. More detailed analysis, including fluorescence in situ hybridization (FISH) or array comparative genomic hybridization (aCGH), may be used to determine the exact size and location of the deletion.

Treatment

There is no cure for Chromosome 5q deletion syndrome, and treatment is symptomatic and supportive. Management may include:

• Blood transfusions for anemia.
• Growth hormone therapy for short stature.
• Physical therapy, occupational therapy, and speech therapy for developmental delays.
• Regular monitoring for the development of myelodysplastic syndrome and other potential complications.

Prognosis

The prognosis for individuals with Chromosome 5q deletion syndrome varies depending on the size and location of the deletion and the severity of symptoms. Early intervention and supportive care can improve quality of life and, in some cases, lifespan.

Epidemiology

Chromosome 5q deletion syndrome is considered a rare disorder, though the exact incidence is unknown. The 5q- syndrome subtype of myelodysplastic syndrome is more common in adults, particularly in women, and has a better prognosis than other forms of MDS.

See Also

• Genetic disorder
• Chromosome abnormality
• Myelodysplastic syndrome