For children of a parent with Huntington's disease, it can be an agonising decision and a long wait to find out if they carry the same gene, writes CLAIRE O'CONNELL
FOR CIARA, the hardest part was waiting. Her father had been diagnosed with Huntington’s disease, a condition where particular brain cells degenerate.
That can lead to involuntary movements, depression and problems with memory, speech and planning. Symptoms often start in middle age, it’s progressive so it worsens over time and there’s currently no cure.
Her father’s diagnosis had been a while coming, recalls Ciara, who is now in her late 20s. It was thought for several years that he was suffering from depression, until a new doctor suggested Huntington’s.
So her father got tested to find out if he had the genetic make-up that underlies the disease.
“That was the worst part, not knowing,” she says. “Then we were waiting for months for the results of my dad’s test and we were thinking what were we going to do if it was a yes.”
When it was a yes, that answered some questions about Ciara’s father’s condition. It also threw open many more.
The genetic “expansion” for Huntington’s disease, where there are too many repeats of certain DNA “letters” in a gene on chromosome four, can be passed on to children.
So if a parent carries it, there’s a 50 per cent or one-in-two chance that each child will inherit it.
That meant Ciara and her siblings faced a hard choice: whether or not to find out if each of them also carried versions of the gene that would lead to the symptoms.
“I wanted to find out straight away,” she says. “But you have to wait for months. They say that at the beginning everyone says they want to know, but then they might change their minds, so you have to wait.”
Then, last year, Ciara, her partner and her mother went in to find out what the test returned. Ciara had what’s termed an “unfavourable result” – she had the genetic make-up to develop Huntington’s disease at some point in her life.
“It sounds funny but I was relieved because I had been waiting so long, I just wanted to know either way,” she says. “That wasn’t the worst moment because then I knew. The bit before thinking ‘Do I or don’t I?’ was horrible.”
While Ciara maintained her wish to know about the Huntington’s gene, about a third of people change their minds, according to Rosemarie Kelly, principal genetic counsellor at the National Centre for Medical Genetics in Crumlin.
“Generally there would be a waiting list from a diagnosis in a family of at least six months,” she explains.
“People want the test, and what you have to say to them is that you may want the test but do you want the result? It could have huge implications, not only for you, but for your family.
“The waiting list provides a ‘cooling off’ period. People get very annoyed over that, but as they go through this process they can understand why. You can’t change your mind once you get the results.”
When a person then starts going for the test, they go through a process, again lasting months, during which they have access to psychiatric support and they can withdraw at any time.
Kelly notes the general under-resourcing in genetic support here, with just five full-time equivalent genetic counsellors in the State.
“We are currently working at 80 per cent below what is recommended by the Royal College of Physicians in the UK,” she says, adding that there is also a lack of specialised community health workers in the State working specifically on Huntington’s disease.
It’s a deficit that’s echoed by Dr Niall Pender, principal clinical neuropsychologist at Beaumont Hospital. “Unfortunately in Ireland the services for people with Huntington’s disease are poor,” he says. “We really are appalling compared to many other countries in the world.”
And he describes the difficulty that can follow a test result: those who get a “favourable result” might experience guilt if their siblings do have the genetic expansion, while those who are predicted to develop the condition could be waiting for symptoms to start. “My heart goes out to people who are having to face into this,” he says.
The Huntington’s Disease Association of Ireland estimates that there are over 500 people presenting with the condition in the State, about 2,500 people are at risk and more than 9,000 family members in Ireland may require support and information.
For Ciara, becoming involved with the HDAI made a big difference to her outlook after getting the result.
Huntington's Awareness Week runs until June 17th. See huntingtons.ie/
