Children with an extra sex chromosome
A study of children aged 5-16 years.
Some children have a sex chromosome trisomy, i.e. instead of the usual two sex chromosomes (XX for girls and XY for boys) they have XXX (girls) or XXY or XYY (boys). Our last study, funded by the NewLife Foundation, involved interviewing parents of a child with a sex chromosome trisomy. We confirmed that, compared with their brothers and sisters, a high proportion of children with a trisomy had been referred for speech and language therapy. We also found that several children had received a diagnosis of autism spectrum disorder. Nevertheless, many children in the study had no developmental or educational difficulties. In our current study we aim to do more detailed genetic and behavioural studies of children with sex chromosome trisomies to try and explain why just a subset seem vulnerable to developing language and communication problems.
In addition, we have been funded by the Nuffield Foundation to devise materials to help parents decide whether and how to tell a child about a sex chromosome trisomy. Further information, and booklets for download, can be found here.
What is the purpose of the study?
Our current study is funded by the Wellcome Trust and we are interested in finding out more about why some children have difficulties with learning to talk, understand or read. People often assume this is caused by a child’s environment. However, our research, and that of others, shows that genetic differences between children can be important. We also have some clues about genes that affect learning to talk and read: individually, these have very small effects, but sometimes a particular combination of genes may have a bigger influence. One thing that does increase the risk of having problems is when a person has an extra copy of a chromosome. We have found that children with an extra X or Y chromosome are more likely than other children to have problems with language, reading or communication. However, every child is different and sometimes the extra chromosome doesn’t have obvious effects. We want to find out whether genes on different chromosomes interact and cause problems in some children. We are very close to our recruitment goal of 150 children, but we still need some more cases of girls with trisomy X (triple X syndrome), and boys with Klinefelter's syndrome (XXY).
It is up to you and your child to decide whether or not to take part. In order to take part we do require that your child is aware that they have an extra sex chromosome. We recommend that parents and their child view a short video about the research before making a decision. We can send a DVD of the video on request, and it can also be viewed here. If you do agree to take part, you will be asked to sign a consent form, but you are still free to withdraw at any time, without giving a reason. A decision to withdraw, or a decision not to take part, would not affect your child’s education or medical care in any way.
What will happen if I give permission for my child to take part?
- One of our research team would telephone you to go through the information sheet with you and answer any questions you have.
- We would also ask you about factors such as your child’s medical history, use of medication, hearing, and educational progress, to check if he or she is suitable for the study. If so, and you are happy to go ahead, we would arrange to come to see your child for an assessment lasting around 2 hours.
- The assessments can be done at school, if the head teacher is willing, but we are also happy to see children at home.
- We assess language by asking the child to repeat words or sentences, or point to a picture to match something that the adult says. We also give a short reading assessment. These tests are digitally recorded for later scoring.
- Some tests look at reasoning using patterns, and do not involve any language. Most of the assessments start with easy items and then get harder. Testing stops when the test gets too difficult for the child.
- We would also do a test to measure blood flow to the two halves of the brain while the child tells a story. This uses a method called transcranial Doppler ultrasound, which is shown on the information video.
- We would also ask you to fill in a questionnaire about communication skills. This takes about 15 minutes. There is also an online questionnaire about general behaviour and development. This takes between 10 and 30 minutes to complete.
- Finally, we would also take a saliva sample from each child for testing DNA as well as from both parents. This is used to look at specific genes that can affect language and reading development. DNA samples will be processed at the Wellcome Trust Centre for Human Genetics.
- Our initial plan is to focus on four particular genes, one of which is found on the X and Y chromosome, to see how they interact. It is likely that in future other genes will be discovered that are relevant to our study. We therefore are asking parents to give general permission for us to use their child’s DNA to look at the effects of genes relevant to children’s development.
- Sometimes the DNA from saliva is not sufficient for analysis. If this happens, we may request a sample of stored DNA (from you or your child) from the clinical genetics department where your child was first diagnosed.
What are the possible disadvantages and benefits of taking part?
There are no risks in taking part in this study. In general, the research does not directly help the children who take part. A benefit is that you could be involved in an important scientific advance and our findings could help children with language or literacy problems in the future. To say thank you for giving up your time, we give participating families a small gift.
Will I get feedback about my child’s results?
We do not usually give detailed feedback. However, if we identify specific language or related problems that haven’t already been picked up, we would discuss this with you and write a report if you wish. We will not in general feed back results from the genetic analysis. However, if we find any genetic factors, over and above an extra chromosome, that substantially increase the risk of language and communication problems, we will describe the results in our newsletter, and give parents the opportunity to request further information about their child’s results.
Will my child’s results be kept confidential?
Questionnaires and test results from our study are identified only by a code number, and kept in a locked filing cabinet. Anonymised digital recordings are stored on a computer. Personal information is kept strictly confidential. DNA is identified only by a code number. Test results and DNA will be made available to other researchers but only through a protected database after removing all information that identifies individual children.
What happens to the results of the research study?
The results will be analysed and reported in scientific journals. Summaries of the findings will be featured in our newsletter.
What happens if there is a problem?
If you have any concern about any aspect of the study, you should speak to the researchers who will do their best to answer your questions. The University is the Research Sponsor for this study. It has arrangements in place in case any harm arises from taking part in the study. If you wish to complain about how you have been approached or treated in the course of this study, you should contact Professor Dorothy Bishop (address above). You may also contact the University of Oxford Clinical Trials and Research Governance Office on 01865 857939, or by email to firstname.lastname@example.org.
What happens when the research study stops?
When the research study stops, we will transfer anonymised results to a public database (dbGAP), where it could be used for future studies. Anonymised DNA will be securely stored at the Wellcome Trust Centre for Human Genetics.
Funding and approval of this research
The study is part of a research programme by Professor Dorothy Bishop of the University of Oxford, and is funded by the Wellcome Trust. This study has been reviewed and given favourable opinion by the Berkshire Research Ethics Committee.
What to do next
If you would like to take part, please telephone us or complete our online form by clicking on the sign up link below. A member of the research team will then get in touch to discuss the study further with you.
How to contact us
If you would like to discuss the research with someone beforehand, or if you have questions afterwards, the first point of contact is:
OSCCI research group
Department of Experimental Psychology, South Parks Road, Oxford, OX1 3UD.
tel: 01865 271386; email: email@example.com.