Dr Jonathan Cohen (Medical Director and General Practitioner, Fragile X Alliance Clinic): Fragile X syndrome is the most common known inherited cause of developmental disability, and the most common single-gene cause of autism. The cause of the syndrome is a result of the expansion or lengthening of a gene on the X chromosome. When the gene lengthens, it switches off production of a protein that is normally vital for normal mental health function.
Dr Randi Hagerman (Behavioural and Developmental Paediatrician, MIND Institute, USA): Everybody has the Fragile X gene, but the mutation that we associate with Fragile X syndrome is an expansion of the front part of the gene. So, in a female who is a carrier of just a small expansion or a pre-mutation, as we call it, their other X is normal. So there’s a fifty-fifty chance that she would pass on the mutated X to her children.
Jonathan: Men who carry the fragile X pre-mutation carry it on their X chromosome. Men have only one X and one Y chromosome. So if they pass their Y chromosome on, that’s going to be to a son. They can never pass on Fragile X to their son. But they will always pass on the Fragile X gene to all of their daughters.
Nyleta (Mother of Connor who has Fragile X syndrome): Connor was diagnosed as mosaic Fragile X, about three months ago. He was diagnosed as part of the process of trying to find out why he was so delayed developmentally. He wasn’t walking or talking or playing like other children would.
Shelley (Mother of Brynn who has Fragile X syndrome): My youngest son Brynn was diagnosed with Fragile X syndrome after his cousin Connor was diagnosed. My sister has a two-year-old who has just been diagnosed with autism. They tested his blood and they found Fragile X, and because it’s genetic we thought we should test Brynn, and he was positive for a full mutation.
Nyleta: The diagnosis of mosaic Fragile X for Connor was a real shock for us, because he’s the first one who’s been diagnosed in the family.
Shelley: When Brynn’s blood test came back, we were devastated. We were straight away thinking about the very worst possible scenario. We read lots of literature and it said lots of things about intellectual disability, and also physical disability. We assumed Brynn was going to struggle and never leave home and not have relationships, and how it would affect us financially. So, it really rocked us to the core I suppose. And then we got to calm down and realised that Brynn is still Brynn, he hasn’t changed. And he is just beautiful. He’s such a smiley little boy. And if he doesn’t develop, it won’t change that he’s still a beautiful person and we love him, and we’ll always love him. So, the initial shock is wearing off, but at first it was very, very difficult.
Jonathan: Fragile X syndrome presents in three main ways: there are physical features, there are developmental features and there are behavioural and emotional features. In terms of the physical features, Fragile X syndrome classically presents with people with a long narrow face, large protuberant ears and a high forehead, although, those features are not always seen. Developmental problems seen in Fragile X syndrome include intellectual disability, also known as cognitive disability, which means they have difficulty understanding the world around them. They can also present with a range of learning difficulties, in particular with areas such as mathematics and other abstract and academic concepts.
Dr Natalie Silove (Developmental Paediatrician, Sydney Children’s Hospital Westmead): The most common behavioural characteristic seen in an individual with Fragile X syndrome is that of anxiety: significant social anxiety, avoidance of eye gaze, and at times withdrawal from social interaction. This can present in many different ways, in other behavioural characteristics. When an individual with Fragile X becomes anxious, they may start rocking, they may hand-flap they may hum or self-talk, and disengage from a particular situation. Many children with Fragile X syndrome struggle with attention. They may have symptoms more consistent with an attention deficit disorder (ADD): very distractible, a little bit hyperactive, and impulsive in some of their behaviours. Speech and language development is often very delayed in children, particularly in boys with Fragile X syndrome. When they do start talking, their words often are sporadic early on, and they then can become very repetitive, in the words that they use or in the phrases that they use.
Shelley: Brynn had a lot of feeding problems. He had severe reflux; he didn’t like to put food in his mouth. He didn’t like a lot of bright light, and noises or too much activity would make him very upset. He’s a rocker, so he does rock a little bit. He’s got low muscle tone, so he’s not walking yet, and he’s a little bit delayed with his speech and his eating, and just that general development delay.
Jonathan: Families who get a diagnosis of Fragile X syndrome are often devastated by the news. It’s very important for families to be aware that providing that they implement the appropriate treatment and management strategies, that their family member can achieve a very fulfilling and healthy lifestyle.
Shelley: They’re beautiful. They’re so happy, and I think sometimes they go through so much more difficulty just living inside their own body and coping with what’s happening to their bodies and figuring out how to grow up. It turns them into very patient, compassionate, beautiful, beautiful children. I think they’re wonderful.