What is Cornelia de Lange syndrome?

Cornelia de Lange Syndrome (CdLS) is a genetic disorder present from birth, but not always diagnosed at birth. It causes a range of physical, cognitive and medical challenges and affects both genders equally. CdLS does not discriminate - it’s seen in all races and ethnic backgrounds. The occurrence of CdLS is estimated to be 1 in 10,000 live births.

Having learned that our child has CdLS was hard to hear but by contacting one of the support groups of the CdLS World, we took an important step. People, mostly volunteers are available by phone or email to offer support, connect us with other families, and provide information from medical, educational and behavioral experts.

People with CdLS can suffer from a range of problems, sometimes very severe and sometimes more mild. Examples of these problems are an intellectual disability, severe bowel and stomach problems causing severe pain and it is life threatening, communication problems causing frustration, self-injurious behavior. It is clear that a good quality of life in under threat of the well-being for both the person with CdLS as well as his/her family members.

Personal witness, why a conference is important

In 1999 our son Rai was born in our town hospital in the Netherlands. After one month the diagnose CdLS was made. Our young family (Rai has a 1 year older sister and later a younger sister was born) was in shock. Research was devastating and people warned us to prepare for the worst. After 6 months, we found support from a CdLS support group, other families in the same situation. This felt like a warm bath; we learned about happy families. We were eager to learn more. How could we help Rai. He had a severe problem from Acid from the stomach, he could cry very long from the pain and was starting to hit himself to block the pain. We decided to visit a world conference to learn more. The Italian expert explained in detail the options we had and we decided to do a surgery. According to the surgeon it was just in time. Since then Rai has been free of that pain and we saw him laughing and playing. For his sisters this was great, they could invite friends as their brother was so 'cute'. We found many friends in the CdLS community.
Last year, 2017, I was attending a symposium where the expert that we also met in the Italy conference many years ago spoke. He told us that in 2006 the major problem in CdLS was self-injury because of pain. I felt so good to hear him say that in 2017 the percentage of people with CdLS showing self-injury because of pain has decreased enormously (almost no cases anymore) because of the conferences and the spreading of information, people got the right treatment against the same problem that my son had at the time.

This is why I can advocate about the importance of being able to attend such a conference! Both families and experts can learn. They talk with each other and bring home a valuable life guide. And by the relationships you make there, you can upgrade your guide each time and we learn new information about this rare disease.

Gerritjan, Father of Rai.

As you know, the 10-th CdLS World Conference will be July 31 – Augus 4 2019 in Bad Neuenahr-Ahrweiler, Germany! This is the 'vereniging’s' and 'Arbeitskreis' signature event, a conference like this happens every two years, organized by different national CdLS groups. This time it is the Netherlands and Germany's turn. 

Families who have attended previous conferences appreciate how much they get out of going and also the efforts to host it. I hope you consider going!
Families attend from all over the Europe (and the World). Each family will get to meet other families from their country, as well as other families with similarly aged children. Each member of your family (mother, father, grandparent, sibling) also will get to interact with similar members of other families. Everyone will be able to choose to attend presentations on clinical, social, and research aspects of CdLS, as well as practical workshops addressing specific issues. Siblings have the opportunity to attend supervised outings with other children.

One of the great benefits of attending Conference is that you and your child can meet with two or more professionals from our Scientific Advisory Council (SAC) for a one-on-one interaction. These experts range from medical professionals (physicians, counselors, therapists, etc.) to educational experts (school, early intervention, etc.) and even researchers. This is a consultation in which your child’s history will be reviewed and specific recommendations will be made. The consultation can be extremely productive, generating recommendations for your physicians, therapists and care providers at home. It is helpful to ask all of your child’s care providers ahead of time if they would like any specific queries addressed.

There is also a scientific/educational symposium held the one day before the family conference, to review and share current and new information related to Cornelia de Lange Syndrome and the science behind it. Some families invite their own professionals to attend the symposium, particularly those who are from Netherlands and Germany. Some even request to shadow our “regular” professionals during the one-on-one interactions, to learn more about the complex world of CdLS; some even become so inspired, they become part of the SAC.

The 'vereniging' and the 'arbeitskreis', in their own way, plans in detail all aspects of Conference for families. This includes: how to help with fundraising prior to going; providing scholarships for first time attendees; tailoring the program for everyone with standard and new information to be shared; organizing the SAC professional consults, planning the many meals; helping the conference committee raise funds to help support the conference both ahead of time and during; and making sure everyone is safe, comfortable, socializing, sharing and not stressing! It’s a truly wonderful meeting, and I highly recommend that you and your family consider attending!

Toni Kline, medical director, CdLS Foundation USA

What is the prevalence in Europe

It is estimated that 1:10000 or 1:30000 people born have a gene mutation that leads to CdLS

With a total population of 740.000.000 (740 million people) we estimate 74.000 (74 thousand) people with CdLS in Europe for 1:10000. (or 25000 = 25 thousand with the more modest estimation of 1:30000)

  • Germany estimated CdLS people 1600
  • Netherlands estimated CdLS people 330
  • Belgium estimated CdLS people 208
  • France estimated CdLS people 1300
  • United Kingdom & Ireland estimated CdLS people 1350

We are seeing far less people connected to a support group (many countries do not have an organized support group, so we believe it is important to send the signal of a conference to these patients. We can only do this with your support. 

Our community around CdLS

This diagram illustrates the effect of the CdLS World website. Note that each support group who has a 'own' website will show 'skewed' in this diagram. But it also indicates which countries are not yet organized (less or equal as 4)

Who are we

We are two family groups from Europe;

  • Germany
  • The Netherlands and Belgium

Both groups have decided in the 2015 conference in Lisbon to jointly prepare a bid for the 2019 conference. This bid was presented to- and unanimously accepted by all members of the CdLS World Federation in the 2017 event in Brazil. The federation represents all support groups around the world.


The Netherlands and Belgium

The group is founded in 1986 by three families from the Netherlands. The goal is to meet each other and to share information. Since 2009 the 'vereniging Cornelia de Lange syndrome' was recognized by the Dutch Government as representing patients and families with CdLS. Because of sharing the same language Belgian families have always participated in the group by sharing stories and attending the family meeting. According to the 1:10000 births 332 CdLS cases are expected in the Netherlands and 208 CdLS cases in Belgium. The group has 125 officially registered members and many partner organizations in the Cure and Care of whom the Cornelia de Lange expertise centre at the Amsterdam University (AMC) is member or the European Reference Network that care about genetic syndromes. 

The bi-annual world conference

Below find a list of imagined packages.

Finacieel overzicht van de pakketten


To get the best information exchange and allow for interactive sessions we need multiple rooms; ranging from a big plenary hall, workshop-sized rooms and rooms for individual consultations. The best impact requires visualization and quality audio equipment. 

  • Organization
    • Organization support
    • Advise
    • Administration
  • Rooms
  • Equipment
    • Audio
    • Video
    • Translation services


40.000,- Euro


The registration of the participants with all the individual selected packages. This must be able in the main languages of Europe (German, Dutch, English, French, Spanish, Italian, Polish)


20,000, - Euro


Sponsor the families with a 'discount' on Hotel


500,- Euro per Family


  • Translation and Interpretation costs
    • English to/from German
    • English to/fom Dutch
    • if necessary French
    • if necessary Italian
    • if necessary Spanish


15,000, - Euro


We need to offer them accommodation and travel and expenses refunds.


16.000 Euro


We need to pay travel and expenses, maybe a fee to get them in our conference


20.000 Euro


During the conference, we would like to provide 1: 1 care for CdLS stakeholders so that relatives can attend lectures and workshops. It is important that these caretakers are optimal supported. 

  • possible nights for Bertreuer
  • Catering
  • Certificate of Attendance


5200, - Euro


We look for attractive elements to add to the program to make it interesting for the siblings;

  • Climbing park
  • Swimming
  • ...


3500,- Euro


As festive, connecting conclusion a gala evening is planned. For music and entertainment such as clown or magician.

  • - DJ or live music
  • - Entertainment program


3500, - Euro


On the first day of the conference, a joint evening is planned for the members of the Scientific Advisory Council and the International Federation to promote acquaintance and exchange. 

  • - Room rental for event
  • - To eat and drink


2000 Euro


For the many participants, parking fees amounting to € 6,500 will be charged on the conference days.

  • - Hotel parking fees
  • - Parking fees for the area


6,500, - Euro


A Bag with logo to carry around all conference handouts and ...


1500,- Euro


All needed to interact with speakers;

  • taking notes
  • devices for interaction


2000,- Euro


Printed materials;

  • Programm
  • Flyers
  • Banners
  • Posters


3000,- Euro


A website to announce the conference including guides


1500,- Euro

Our financial plan

Kent and Marcel to complete this part

Our approach for fundraising

To raise the money required to organize this very important event both the 'Arbeitskreis' and the 'Vereniging' will use funds from their own yearly budget (e.g. the 'vereniging' will put aside 30.000 Euro of their yearly budget.)
The Netherlands will also ask our members to consider a one-time extra donation of 100,- budgeted to 50 x 100 = 5.000 Euro.

We will approach funds to sponsor the B1. Special needs care for people with CdLS, B2. Attractive program for siblings, B4. Great closing Event (Gala), B5. Events to celebrate volunteers (SAC, Federation, Volunteers) budgeted for 15.000,-

We will also organize a social media campaign for each individual member in Germany, Belgium and the Netherlands to allow them to collect money for attending the conference and pay for the hotel. If each family could get 500,- to 1000,- (depending on number of family members). We are aiming for 250 participants (= 100-150 families ) at a minimum.

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