CdLSFrequentlyAskedQuestions
- What is a syndrome?
- "Syndrome" is a medical term for a condition in which there is a collection of signs (observable body changes) and symptoms (problems observed by the patient) recognizable by a doctor's exam. Individuals with a syndrome may not have all of its associated signs and symptoms, but they must have enough to be considered "diagnostic." Conversely, because someone may display some of the signs and symptoms of a syndrome, does not necessarily mean they have it.
- How is CdLS recognized?
- CdLS is a congenital syndrome, meaning it is present from birth. Most of the signs and symptoms may be recognized at birth or shortly thereafter. A child need not demonstrate each and every sign or symptom for the diagnosis to be made.
As with other syndromes, individuals with CdLS strongly resemble one another. Common characteristics include: low birthweight (often under five pounds), slow growth and small stature, and small head size (microcephaly). Typical facial features include thin eyebrows which frequently meet at midline (synophrys), long eyelashes, short upturned nose and thin, downturned lips.
Other frequent findings include excessive body hair (hirsutism), small hands and feet, partial joining of the second and third toes, incurved fifth fingers, gastroesophageal reflux, seizures, heart defects, cleft palate, bowel abnormalities, feeding difficulties, and developmental delay. Limb differences, including missing limbs or portions of limbs, usually fingers, hands or forearms, are also found in some individuals.
En 1933, le Dr Cornelia de Lange, pédiatre néerlandaise, a décrit deux enfants présentant des caractéristiques similaires, l'un âgé de 17 mois et l'autre de 6 mois, qui ont été admis à quelques semaines d'intervalle à l'hôpital pour enfants Emma. Le premier enfant souffrait d'une pneumonie. Sa première année de vie avait été caractérisée par de nombreuses difficultés d'alimentation et elle était très petite pour son âge, avec un périmètre crânien proportionnellement plus petit.
D'autres caractéristiques faciales inhabituelles ont été notées par le Dr de Lange. Peu après la sortie de cette enfant, une deuxième petite fille a été admise. Non seulement elles avaient des problèmes médicaux communs, mais leur ressemblance était remarquable. Dans chaque cas, le médecin a décrit ce qu'elle a observé avec beaucoup de soin et de détails.
How many people have CdLS?
The exact incidence is unclear, but it is thought to be approximately 1 in 10,000 live births.
Is life expectancy known?
It is expected that most children with CdLS will live well into adulthood; however, each child must be evaluated for life-threatening conditions such as heart defects, untreated gastroesophageal reflux, and bowel abnormalities.
- What causes CdLS?
- Researches have identified genes that, wen altered, cause CdLS. Please see the genetic information for more details about these discoveries.
- Genetic Information
- In 2004, researchers at The Children’s Hospital of Philadelphia and the University of Newcastle upon Tyne, identified the location of genes that causes Cornelia de Lange Syndrome, or CdLS, when it is mutated or changed.
In the journal 'Nature Review Genetics', the latest insights on, among other things, the Genetics of CdLS by an international group of experts (a.o. Dr Frank Kaiser) were published in July 2018.
The genetic causes of CdLS are complex and research to understand all the genetic causes is ongoing. A child's DNA profile cannot be changed after conception.
The CdLS spectrum is associated with a change (mutation) in the genetic material. Usually, CdLS is caused by a change in one of seven genes. Genes are individual genetic instructions in the DNA that make us who we are. The seven genes associated with CdLS are: NIPBL, SMC1A, SMC3, RAD21, BRD4, HDAC8 and ANKRD11
Why it is important to have found the CdLS genes
- To confirm the diagnosis
- To understand the diagnosis of CdLS, improve existing therapies, and design new medical therapies
- To understand the role these gene changes play in development
- To offer reassurance, through genetic testing, that other family members are not affected
- To provide accurate information and counseling resources for future pregnancies
- To generate broad interest about the syndrome in the medical/scientific research community
- Is CdLS hereditary?
- Not in the usual sense of a gene passing directly from parent to child. Genetic changes (called mutations) occur in individuals with CdLS that typically are not present in their parents, meaning that a new change developed in those individuals resulting in CdLS.
In a few rare families who have more than one child with the syndrome, each of the children with CdLS has had the same mutation, which has not been found in any unaffected family members. This gene is almost never passed on to the next generation because affected individuals seldom have children of their own. There are tests which may help resolve some of the uncertainty felt by CdLS families with future pregnancies. Genetic counseling centers are able to provide current information on testing.
Can CdLS be detected before birth?
There are tests which may help resolve some of the uncertainty felt by CdLS families in future pregnancies. High resolution ultrasound may be useful to monitor for unusually poor fetal growth or detectable limb abnormalities. Genetic counseling centers are able to provide current information on the development of other prenatal tests.
How is a diagnosis made?
The diagnosis of CdLS is primarily a clinical one based on signs and symptoms observed through an evaluation by a physician, including a medical history, physical examination, and laboratory tests. This is best accomplished through a referral to a genetics specialist or clinic.
I think my child has CdLS, what can I do?
If you suspect that your child has CdLS, you should arrange for an evaluation by a genetics specialist. Arrangements can usually be made through your local physician, hospital, or university medical center.
If my child has CdLS, what can I expect?
Each child will progress at his/her own rate, but you can generally expect a slower than average rate of physical and cognitive development. The area of speech and communication is often delayed, even in the more mildly affected. Infant stimulation programs and other developmental and therapeutic interventions are strongly recommended. Growth and development charts are available.
