5q14 Micro deletion syndrome
This condition is caused by missing genes (also called a deletion) on one copy of chromosome 5. The deletion is suggestive of a recently characterized condition known as 5q14 deletion syndrome, which is characterized by intellectual disability, seizures, and hypotonia.
There is no cure for this condition, but having a diagnosis can help guide a person’s health care. Currently, the clinical findings associated with this deletion are not well-defined, and there are currently no clinical guidelines for doctors based on this deletion. However, we may learn more about this deletion over time.
5q14 deletion syndrome has been associated with many features. These are likely to range in severity from person to person (variable expressivity). Given that so few people with 5q14 deletion syndrome have been reported, it is difficult to provide detailed information on the clinical findings associated with this deletion. However, we can provide some information about the clinical features reported in multiple people.
Most people with 5q14 deletion syndrome have decreased muscle tone (hypotonia). This can affect their ability to develop skills such as learning to walk. In addition to delays in motor development, people with this condition often have absent or delayed speech. Seizures are another frequent feature in people with 5q14 deletion syndrome. A variety of structural brain abnormalities found by brain MRI have also been reported.
A person with 5q14 deletion syndrome typically has subtle, unique physical features. However, it may be difficult for someone other than a genetic specialist to recognize them. These features include a high and wide forehead, pronounced eyebrows, a short and/or prominent philtrum (space between the nose and upper lip), downturned corners of the mouth, a small chin (micrognathia), and structural ear abnormalities. These features generally do not cause medical problems but lead health care providers and parents to suspect that the child has an underlying medical condition.
It is thought that all people with 5q14 deletion syndrome will have some degree of intellectual disability; this can vary from mild to severe. Additionally, many of those with 5q14 deletion syndrome have stereotypic movements and avoid making eye contact which may lead to a diagnosis of an autism spectrum disorder.
5q14 deletion syndrome is a rare condition that has only recently been characterized; therefore it is difficult to pinpoint just how often it occurs. This is because there is a wide range of features, and some people with milder features may not be recognized. Most deletion syndromes affect people of all ethnicities and both genders equally; so, it is expected for this to be the case with 5q14 deletion syndrome. At present, this deletion has been reported in less than 50 people. It is thought that genetic variations of the MEF2C gene, including deletions, may account for up to 1% of people with intellectual disability.