One chromosome: a world of difference

Children with a sex chromosome abnormality should be diagnosed as early as possible.  This is what Veni winner Sophie van Rijn advocates.  Currently, the condition often goes unnoticed, with the risk that the child’s cognitive and social problems pile up unnecessarily.

That is a pity, says the Leiden neuropsychologist, because the disturbance to social development has  by then already had an effect.  During her PhD research, she studied adult males with Klinefelter synrome. ‘Many of these men do not pick up subtle social signals,’ explains Van Rijn.  ‘They may, for example, tell some long story without noticing from the face of the person they are talking to that their interest is lost at a certain point.  This can make it difficult for them to make friends and to maintain good relations with work colleagues.  This can lead to psychological problems such as depression and anxiety.’

Early intervention

These effects can probably be prevented if the condition is detected at an young age,’ in Van Rijn’s opinion. ‘If you know that a child is suffering from Klinefelter or Turner syndrome, you can offer him or her good support at home and at school.  This will prevent the problems from piling up. 

Currently, very little is known about the underlying mechanisms which lead to disturbed social development among children with a sex chromosome abnormality. ‘This is a good challenge for me as a researcher,’ says Van Rijn. ‘If we understand better what goes wrong with children, we can in future recognise the condition at an earlier stage and adapt our support to suit their specific needs.’

A great deal of research has already been conducted into autism.  Because Klinefelter and Turner syndromes have similar symptoms to their better-known fellow autism, in the broad spectrum of the development disturbances, it is tempting to assume that the underlying mechanisms are the same.  According to Van Rijn, these conclusions are premature.  ‘There are many reasons why children may have difficulty with social situations.  Earlier research among adults has shown that people with Klinefelter syndrome have difficulty with processing language, while people with Turner syndrome lag behind in the social-spatial domain.  This is the line of research I intend to pursue with my Veni subsidy.  I want to chart the different aspects which may lead to social handicaps.’

To achieve this, Van Rijn will also be taking a look into the brain.  Using the latest neuro-imaging methods, she will be able to see which areas of the brain light up when processing social information.  She wants to examine, for example, what happens in the brain when children with Klinefelter or Turner syndrome are required to recognise a facial expression. These children will be using different strategies for this – linguistic or visual – which activate different areas of the brain.

If this is indeed the case, it offers some perspectives for guidance for these children. Van Rijn: ‘A child with a sex chromosome abnormality needs specific attention to be paid to his strengths and weaknesses.  A child with Klinefelter syndrome can, for example, be helped to deal with social situations by explaining using pictures and other forms of visual support.  This may well work better than a verbal explanation.’ Some colleagues of Van Rijn are currently working on developing various cognitive training programmes which they will be testing for effectiveness on different groups of children.  This would enable guidance for children with social problems to be much more focused and effective. 

Van Rijn’s research is not only progressive in a practical sense; it is also in her style of thinking that she treads unexplored territory.  ‘In fact, I turn classical clinical thinking around,’ says Van Rijn.  ‘I don’t stick a label on particular behavioural symptoms, and then go on to examine them.  Instead, I start with the cause, a genetic defect which is easy to establish, and then I look at what its effects might be on the development of the brain and on behaviour.’

These effects are not fixed in advance and may vary from person to person, Van Rijn stresses. ‘A person with a sex chromosome anomaly is not doomed to go through life with major problems.  Simply because problems may have a genetic cause, this does not mean that they are unavoidable and unchangeable. With the right support from the surrounding environment, you can help children with their development.  The earlier, the better.’

To be able to offer this support, an early diagnosis is essential.  Van Rijn therefore finds it regrettable that there is currently no standard check on sex chromosomes in new-born babies.  A missed opportunity, according to this Veni winner.  ‘You cannot take away an extra X chromosome and you can’t replace a missing X chromosome, but you can have a positive influence the effects of the condition.  Why should be deny ourselves this opportunity?’

(Source: Leiden University: September 2008)