How did this all start?

The mother of a child with a chromosome 6 aberration who attends our clinic told us about the active international chromosome 6 patient group on Facebook. Encouraged by this mother, we came up with the idea to launch a study of chromosome 6 deletions and duplications through this already large and still growing Facebook group.

The study of chromosome 6 can serve as a blueprint for studying other rare chromosomal disorders, as well as other types of rare disorders where there are a small number of patients distributed world-wide.

Why is this project important?

There are many possible chromosome 6 aberrations, each with different symptoms, and all of them are extremely rare. Because of the broad variety of chromosome 6 alterations, there is little information available for each specific aberration, leading to uncertainty for parents and doctors and sub-optimal treatment for affected children.

What are chromosome 6 aberrations?

Individuals with a chromosome 6 aberration have too little or too much material on chromosome 6. Too little chromosomal material is called a deletion; too much is called a duplication.

How are chromosome 6 aberrations detected?

Chromosome 6 aberrations are detected by detailed chromosome analysis. Such a test is often performed when a child has developmental problems and/or birth defects. You can find more information on detailed chromosome analysis and how to interpret such a result on the ‘Detailed chromosome analysis’ page.

What is already known about chromosome 6 aberrations?

Chromosome 6 aberrations can cause all sorts of medical and developmental problems. In the pilot project (2013), we investigated what is already known about chromosome 6q deletions in the literature and compared it to the information from the chromosome 6 Facebook Group. A summary (‘sneak preview’) of the findings in the pilot project can be found in the older news items.

In addition, Unique – the rare chromosome parent organization – publishes ‘Rare Chromosome Disorder Guides’. You can find these booklets about chromosome 6 deletions and duplications on

 What is our final goal with this project?

We want to compare the exact aberrations in chromosome 6 (the genotype) with the effect these genetic changes have on the appearance and other clinical symptoms of the individual (the phenotype). In this way we hope to link specific disease characteristics with specific regions of chromosome 6. This may allow us to predict the clinical effect of certain deletions and duplications, and learn about the functions of the many genes that are located on chromosome 6.

To achieve this we have designed a web-based questionnaire to collect information on people with chromosome 6 deletions and duplications. This information will be analysed and the results made available (anonymously) via publications on the Chromosome 6 Facebook page, in patient information leaflets (in collaboration with Unique, a patient organisation), and in medical journals.

In the future, we hope to be able to create an interactive webpage with a detailed map of the genetic information and symptoms of chromosome 6 disorders, i.e. a genotype-phenotype map. This information can be used by parents and professionals to give tailored advice to patients.