HD-Africa May 9th 2021
Author: Grace Njoroge, the newest member of HD-Africa with a passion for Genetic counselling and rare disease advocacy
The human brain has eighty-six billion neurons, also called nerve cells, that are responsible for receiving and sending signals from the brain to other tissues like our muscles. Progressive degeneration of these nerve cells results in Huntington’s Disease (HD) which is caused by a defective gene, the huntingtin (HTT) gene. Huntington’ Disease often leads to movement, thinking (cognitive), and psychiatric disorders.
Huntington’s Disease is an inherited disorder that is transmitted when a defective HTT gene is passed on from parent to offspring. Symptoms usually appear between the ages 30 and 50 and become worse over a 10 – 20-year period. The Disease could also develop before the age of 20 and is referred to as juvenile Huntington’s Disease. Huntington’s disease has a wide spectrum of symptoms that are classified as movement disorders, affecting both voluntary and involuntary movements such as jerking, impaired posture, and balance. Other symptoms are grouped as cognitive disorders, affecting learning, memory, perception, and problem-solving. The last category of symptoms encompasses Psychiatric disorders, whose main manifestation is depression.
Rare Diseases, like Huntington’s Disease, take a long time to accurately diagnose, in what is commonly referred to as a diagnostic odyssey. In the case of HD, primary diagnosis involves a general physical examination, neurological examination, and genetic testing.
Huntington’s Disease currently has no cure or effective treatment options; however, some symptoms can be managed. As discussed in our previous blog, in future it will be possible to regulate the production of the mutant Huntingtin protein, through gene therapy. This could offer hope for managing and slowing down of the symptoms. There are various companies at the forefront of gene therapy research on HD including, uniQure, Spark Therapeutics, Roche, Voyager Therapeutics, and Sanofi Genzyme.
A study on the epidemiology of neurodegenerative diseases in Sub-Saharan Africa , revealed that between 1955 and 2012 only 144 studies on these diseases had been conducted and published. Of these, only 19 publications reported on Huntington’s Disease. These 19 studies were conducted in South Africa (nine studies), Zimbabwe and Tanzania (two studies each), Nigeria, Mauritius Island, Senegal, Sudan, Togo, and Burkina Faso (one study each).
More research needs to be conducted on the case of Huntington’s Disease especially in the Sub-Saharan population. HD-Africa, the continent’s flagship Huntington’s disease advocacy body, was launched to address the need for more research and to illuminate the invisible HD population that comprises Sub-Saharan Africans. HD-Africa provides information on the patient support groups available in Africa – currently in Kenya and South Africa, resources on how to find a neurologist in Kenya, and an updated list of research on HD .
Reportedly, South Africa has the largest research output on Huntington’s Disease in the continent. Universities like the University of Cape Town carry out research on HD as well as provide genetic counseling for patients. Patient support groups like the Huntington’s Association of South Africa (HASA) and the Huntington’s United Group of Gauteng in the Republic of South Africa provide support and encouragement to individuals and families affected by Huntington’s disease.
There is little to no research on Huntington’s Disease in most African countries. To address this, HD-Africa seeks to advocate for HD in Africa, to connect with affected families, and spur work that will result in high quality research, training of professionals and care for affected individuals.