A genetic disorder is caused by one or more abnormalities in the genome. Examples of recognised disorders include Down’s syndrome, Angelman syndrome, Prader-Willi syndrome, Williams syndrome and Rett syndrome.
However, as more sophisticated methods of analysing people’s chromosomes and DNA become available, like microarrays and DNA sequencing, many more children are receiving a diagnosis of a rare chromosome disorder or an autosomal dominant single gene disorder. Often there is little known about the condition, which may not even have a name, and with only a few individual’s living with the condition, little is understood about the children’s development and prognosis. Fortunately, the rapidly expanding field of genetic research is increasing awareness of rare chromosomal disorders.
For further information, visit www.rarechromo.org.
Down’s Syndrome is a chromosomal disorder called Trisomy 21. It is not hereditary and can occur in all families, though it is more likely with older parents. The abilities of children with Down’s Syndrome vary enormously, but most tend to be within the mild to moderate learning disability range.
Diagnosis is confirmed via a pre-natal blood test called a chromosomal karyotype.
About 750 babies with the condition are born in the UK each year – around one in every 1,000 births.
Children with Down's Syndrome have a lot to offer. They are friendly, cheerful, kind and trusting but they will experience a range of difficulties and problems too. Potential difficulties and disabilities include learning disability, poor muscle tone; developmental delay; speech and language delay, and speech is often indistinct, owing to the atypical mouth formation; congenital heart disease; vision disorders; middle-ear problems; and conductive hearing loss. However, children with Down’s syndrome do develop communication skills and can learn effectively.
The developmental gap between children with Down’s Syndrome and typically developing children widens with age - so children with Down’s Syndrome may cope well in mainstream primary schools but find the demands of secondary school problematic.
Parents of children with Down's Syndrome are often concerned that their child will be bullied or picked on. Experience suggests that the reverse is often true; children who have been perceived to be prone to this kind of behaviour have responded by offering support and protection to the less able child.
What can help?
- Time - a child with Down's Syndrome will take longer than most to process information.
- Practice - they require more practice when learning skills. Some learning may never be completely mastered.
- Teaching methods - these should include visual as well as linguistic clues to help learning.
Choosing a school
A good school will:
- Listen to parents' concerns.
- Seek outside information from expert sources on the learning and other needs of children with Down's Syndrome.
- Look at your child's inclusion as a matter of right.
- Seek to offer access to a broad and balanced curriculum.
- Be creative at finding ways to include your child in the whole range of school life.
With sensible differentiation, assessment and tools for measuring and celebrating individual achievement, children with Down’s Syndrome can be successfully included throughout their infant and primary education. However, at transfer to secondary school only 27 per cent currently continue in mainstream. The increasing complexity of the curriculum can make it difficult to learn alongside their peers, and unless a mainstream secondary offers an additional needs unit where they can study at their own pace, many children will continue to need good special school placements through to transition into further education.
For further information, visit www.downs-syndrome.org.uk.
Angelman Syndrome (AS) is a rare condition, affecting one in 15,000-people. It shares symptoms with autism, cerebral palsy and Prada-Willi Syndrome, and is sometimes mistakenly diagnosed as such.
Symptoms of Angelman Syndrome
AS children characteristically have a happy, excitable demeanor, other features include small head, sometimes inappropriate laughter, stiff jerky movements and a tendency to extreme thinness. Other characteristics include sleep problems, lack of speech (greater receptive than expressive language), and developmental delay.
Current treatment focuses on managing the medical and developmental issues.
For further information, visit www.nhs.uk/conditions/angelman-syndrome.
Prader-Willi Syndrome (PWS) is a rare condition, affecting one in every 15,000 people. It is recognised as the most common genetic cause of life-threatening childhood obesity.
Symptoms of Prader-Willi Syndrome
PWS is often characterised by an insatiable appetite for food and tendency to gain weight very rapidly. Other characteristics include poor muscle tone, co-ordination and balance; emotional and social difficulties; immature physical development; immature development of sexual organs (few reach full sexual maturity); behavioural and learning difficulties.
As with Down’s Syndrome, many people with PWS also exhibit distinctive facial and other physical features. These include small hands and feet, almond-shaped eyes, a narrow forehead and a down-turned mouth with a triangular-shaped upper lip.
There is no cure for PWS, although management of the symptoms and associated problems is necessary. The Prader-Willi Syndrome Association UK recommends the help of a dietitian, paediatrician, physiotherapist, educational psychologist and (if necessary) speech therapist.
For further information, visit https://www.pwsa.co.uk.
Williams Syndrome is a rare condition that affects intellectual development, occurring in one in every 10,000 people. There may be associated physical problems ranging from slight muscle weakness to heart defects.
Symptoms of Williams Syndrome
As with Down’s Syndrome people may have a facial similarity. They are characterised by ‘elfin’ features – a wide mouth, turned-up nose with flattened bridge, slightly puffy cheeks and widely spaced irregular teeth. Some may have a squint. Initial signs of Williams Syndrome include low birth weight, slow weight gain, below average growth, missing developmental milestones, slow feeding, restlessness, hyperactivity and possible excess vomiting. A raised calcium level is found in some babies.
Older children may demonstrate uninhibited, inappropriate behaviour, and feel compelled to talk to adults but unable to relate to their peers. They may have obsessional interests, a short attention span, exaggerated emotions, emotional immaturity, poor motor skills and learning difficulties but with a high verbal ability. Heart problems are common as all sufferers have a narrowing of the aorta. Most notable of all is a hypersensitivity to noise, eg becoming distressed by balloons bursting, while many have a passion for music
Learning difficulties may make mainstream education problematic, but if a child is placed in a special school, it is important to ensure it can provide the stimuli of verbal communication and social interaction.
For further information, visit https://williams-syndrome.org.
Rett Syndrome, a complex neurological disorder, is probably the most common genetic cause of profound intellectual and physical disability in girls (it mainly affects females), occurring in more than one in 12,000 female births.
Symptoms of Rett Syndrome
Most people with Rett Syndrome have profound and multiple disabilities with high dependency needs throughout life.
Typically a child will appear to be making normal progress, but with a period of stagnation in development from about the end of the first year until regression occurs (a regression period occurs when skills in speech and hand movement are reduced - usually between 9 and 30 months); development of repetitive hand movements such as wringing, patting, clapping, tapping or mouthing; a stiff or clumsy posture, or an unsteady, wide-based gait; and a slowing of head growth between 2 months and 4 years.
Other features include breathing irregularities such as hyperventilation, breath holding and air swallowing; EEG abnormalities; epilepsy; with age, muscles become increasingly rigid, and there may be joint deformities and muscle wasting; development of scoliosis (curvature of the spine); and growth retardation. A child may not have all these features, and the age at which symptoms appear varies.
For further information, visit https://www.nhs.uk/conditions/rett-syndrome.