Huntington's Disease Rare in Young Children Like Kathleen Edward
Nine-year-old Kathleen Edward, who received national attention after she was cyberbullied on Facebook because she had Huntington’s disease, lost her battle with the terminal disease on January 11. Her courageous fight focused light on a disease that is rare in young children but nonetheless just as deadly as when it hits adults.
Kathleen’s mother had Huntington’s disease
Huntington’s disease cannot be “caught” like the flu or the measles: it is an inherited disease caused by a genetic defect that causes a part of DNA (a CAG repeat) to occur more than it should. CAG refers to three of the four bases found in DNA (C=cytosine, A=adenine, G=guanine).
The more the defective gene is passed down through the generations in families, the greater the number of CAG repeats. As the number of repeats grows, so does the chance of developing symptoms of the disease at a younger age.
In 2009, Kathleen’s mother, Laura, also succumbed to the disease, according to CBS News reporting. Adult-onset Huntington’s disease is the most common form, and individuals who are affected typically begin experiencing symptoms in their mid 30s and 40s. Most patients survive with the disease for 10 to 25 years after onset.
Huntington’s disease is also known as Huntington’s chorea because of one of its main characteristics is sudden and often wild jerking movements of the limbs, face, and other body parts. "Chorea" is derived from a Greek word meaning "dance."
Only 5 to 10% of cases of Huntington’s disease occur in people younger than 20, according to the National Institute of Neurological Disorders and Stroke. Children with this form of Huntington’s, sometimes referred to as juvenile Huntington’s, usually inherit the disease from their father. People with adult-onset disease typically inherit the defective gene from their mother.
The Huntington’s Outreach Project for Education, at Stanford (HOPES) notes that the symptoms of juvenile Huntington’s differ from those of adult-onset disease. Children typically have rigid or stiff movements rather than the twisting and turning movements (chorea) characteristic of older patients. About one-third of children also experience recurrent seizures, an uncommon symptom in adults.
However, like adults with the disease, children experience a progressive loss of mental function and personality changes, such as irritability and moodiness, as well as symptoms associated with neurological damage, such as difficulty swallowing and speaking.
Treatments for Huntington's include medications such as anticonvulsants and sleeping aids to ease the symptoms, and physical therapy, which can help with rigidity. A recent study reported by researchers at the University of California, Los Angeles, noted that coenzyme Q10 may be helpful in slowing the disease progression, but so far only animal studies have been conducted.
So far there is no cure for Huntington’s disease. The prognosis for children with juvenile Huntington’s is less than 10 years, and in Kathleen Edward’s case, her battle ended before the decade mark.
Hickey MA, Zhu C, Medvedeva V, Franich NR, Levine MS, Chesselet MF. Evidence for behavioral benefits of early dietary supplementation with CoEnzymeQ10 in a slowly progressing mouse model of Huntington’s disease. Mol Cell Neurosci 2011 Oct 20; 49(2): 149-57
Huntington’s Outreach Project for Education, at Stanford
National Institute of Neurological Disorders and Stroke
Picture credit: Wikimedia Commons