5q14.3 Deletion Syndrome

February 28th was Rare Diseases Day. According to the Rare Disease site, to be considered a rare disease, the illness must have less than 2000 confirmed cases, affect less than six percent of the world’s population, and typically be genetic. There are 300 million people suffering from these rare diseases today. One such rare disease is 5q14.3 Deletion Syndrome. 

The 5q14.3 Deletion Syndrome severely affects cognitive abilities, makes one unable to speak and specific movements associated with it, and may cause epilepsy. Children with this disease often have distinct facial features: high, broad foreheads, small chins, small noses with nostrils that open in the front instead of downward, larger mouths, eyes that point downward at the outside corner, and striking eyebrows. Since 5q14.3 Deletion Syndrome is a chromosome, one must look at what causes disorders of the chromosomes. 

A chromosome is where the genes of a person are found. Some chromosomes have “arms,” with the shorter being called “p” and the longest being called “q.” These chromosomes are located in the nucleus of the cells. There are 23 pairs of chromosomes with at least 20,000 genes in the human body. One cause of these disorders is when cells copy themselves, called “mitosis.” The opposite can also occur in “meiosis,” in which the cell only has half the number of chromosomes. The latter only happens in the reproductive organs of a person. 5q14.3 Deletion Syndrome affects the MEF2C gene, and the number 5 chromosome has deletions in the 5q14.3 section, which causes the decline of cognitive abilities and specific physical characteristics. 

Due to its rarity and high rates of misdiagnoses, the incident rate of 5q14.3 Deletion Syndrome is currently unknown. Anyone can be affected by it; however, one of the risks associated is “a positive family history.”  Other than that, there have not been enough cases to establish any patterns of either predisposition to the disease versus external factors contributing to the contraction of the disease. The prognosis depends on the severity of the syndrome and varies from case to case. Some children have mild cases and live relatively everyday lives with continuous treatment. Others with more severe symptoms may require lifelong care, which can worsen as they age. Children missing the MEF2C gene often have a worse prognosis than those who are not missing it, leading to more aggressive symptoms and a quicker decline in life quality. 

The first step to diagnosing Deletion Syndrome is a thorough physical examination. Next, the doctor assesses any evident symptoms of the disorder, as well as hearing, vision, and cardiac tests. Lab tests and radiology tests are run as needed. Brain scans may be done if the child’s brain is developed, along with neurological testing. Behavioral, prenatal, and genetic testing may be conducted to ensure the doctor has captured a complete picture of the patient’s biological chemistry and symptoms. The doctor or specialist may perform other tests to rule out disorders with similar symptoms before officially diagnosing someone with 5q14.3 Deletion Syndrome. Sadly, even after running all the necessary tests, doctors are often unfamiliar with Deletion Syndrome and can easily misdiagnose people’s conditions.

There is currently no cure for 5q14.3 deletion syndrome, but treatment is given to help control the symptoms. To assist with impaired hearing, children may receive hearing aids, be taught sign language, or attend speech therapy. Antiseizure medication may be used to help control seizures. Physiotherapy can help with weak muscles, along with mobile devices such as canes, walkers, or wheelchairs. For children who have trouble eating, feeding tubes and specific diets, including unique formula, may be needed. Psychotherapy and occupational therapy may be given. These are some of the treatments that are used for a child with 5q14.3 deletion syndrome. 

While rare diseases affect fewer people than more common illnesses, they are just as important. With Rare Diseases Day, I ask you not to dismiss this or any other rare disorder because it is rare. Instead, think about the people currently facing the challenges associated with rare diseases and consider ways to raise awareness for these less common illnesses.  

For More Information on Rare Diseases, visit the Genetic and Rare Diseases (GARD) Information Center