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18q Syndrome

What is 18q syndrome?

18q syndrome is a chromosomal disorder that causes a variety of physical and mental symptoms. It is a very rare disorder, with more than 80 cases being reported since its discovery in 1964. Females are also more likely to be affected than males. 

What are the symptoms of 18q syndrome?

Symptoms and severity can vary widely between individuals. The majority of affected individuals are born with a low weight and height, which leads to short stature. They also experience low muscle tone, malformations of the skull, deeply set eyes, a carp-shaped mouth, clefting of the palate, a broad nasal bridge, a cleft lip, and a protrusive lower jaw. 

Mental retardation is another characteristic symptom, and it may be accompanied by aggressive actions and behavioral issues. Seizures, delays in developmental milestones, ocular impairments, vision loss, and issues with the ears and hearing are other symptoms. 

Other physical abnormalities include:

  • Long and thin hands
  • Abnormal skin patterns on the fingers and hands
  • Clubfeet
  • Abnormal placement of the thumb and/or toes
  • Skeletal defects (these can occur in the hips, ribs, and other places)
  • Abnormal dimples
  • Genital abnormalities

In some cases, additional symptoms have been reported. These include a deficiency of immunoglobulin A, other physical abnormalities, and heart defects. 

What causes 18q syndrome?

This syndrome is caused by a deletion on the long arm of chromosome 18. In the majority of cases, this deletion is caused by a spontaneous mutation that occurs very early in the development of the embryo. 

How is 18q syndrome diagnosed?

In many cases, 18q syndrome can be diagnosed before a child is born. This is done through ultrasounds, chorionic villus sampling, and amniocentesis. After the baby is born, doctors will conduct a physical exam and chromosomal analysis to confirm a diagnosis. 

What are the treatments for 18q syndrome?

Treatment is symptomatic and often requires a team of specialists. Surgery may be necessary for skeletal abnormalities, corrective lenses can help with vision issues, and hearing aids may help with any hearing loss. Anticonvulsants are also commonly prescribed. Regardless of the treatment, it is best if it is administered early. 

Where can I find out more about 18q syndrome?

18q Syndrome Articles