Date of publication: 2009-02-26
Version: 2.2
22q11 deletion syndrome leads to disturbances in embryonic development that can affect several organs in the body. The severity of the various symptoms ranges from very mild to profound. A number of congenital defects may occur, such as heart defects, cleft palate, and underdeveloped thymus or parathyroid glands. The disorder may also involve other, more rare, defects. Common symptoms are feeding difficulties, speech problems, frequent infections, learning difficulties, and neuropsychiatric abnormalities. Teeth, hearing, vision, and growth may also be affected.
22q11 deletion syndrome is also known by several other names: velo-cardio-facial syndrome (VCFS), DiGeorge syndrome, and CATCH 22.
DiGeorge syndrome was described in 1965 by paediatrician Angelo DiGeorge, from Philadelphia. The characteristics of the syndrome included immunodeficiency caused by an underdeveloped thymus, low blood calcium levels owing to impaired functioning of the parathyroid glands, and characteristic heart defects.
In 1978, Robert Shprintzen, a New York speech pathologist, described a syndrome in which the palate functioned abnormally, and was sometimes cleft. This syndrome was characterised by speech abnormalities with hypernasal speech, congenital heart defects, learning difficulties, and a characteristic facial appearance. Shprintzen named this syndrome velo-cardio-facial syndrome (VCFS, velo= roof of the mouth, cardio = heart, facial = of the face).
In the early 1990s, it was found that one and the same chromosome aberration, the 22q11 deletion, caused both syndromes. They were thus found to be different manifestations of the same chromosome deletion.
In 1993, a group of British researchers proposed an entirely new name for the syndrome, CATCH 22, which is an acronym in which C stands for Cardiac anomaly, A for Anomalous face (the characteristic appearance), T for Thymic hypoplasia (underdeveloped thymus gland), C for Cleft palate, H for Hypocalcaemia (low blood calcium level), and 22 for chromosome number 22.
Although the appellation CATCH 22 has previously been widely used, 22q11 deletion syndrome has now become an established name internationally as well as in Sweden.
Approximately one out of 4 000 children is born with a 22q11 deletion. This means that in Sweden at least 20-30 children are born with the syndrome every year. To date, 200-300 individuals have been diagnosed in Sweden. Since recognition of the syndrome is relatively recent and many individuals have only mild symptoms, there is every reason to believe that there are a great many undiagnosed cases, and that the actual number of people with the syndrome is substantially larger.
The syndrome is caused by the deletion (loss) of a very small segment of the long arm of one of the chromosomes in the number 22 chromosome pair (22q11). In other words, a small part of the genetic material from this region, along with the information it should have encoded, is missing.
Many research groups have tried to identify which genes and genetic mechanisms cause the characteristic symptoms of the disorder. Several researchers have shown that out of the approximately 25 genes that are missing, there is a gene known as TBX1 which can explain certain aspects of the syndrome. The TBX1 gene codes for the Tbox1 protein which is important for the formation of certain tissues and organs during fetal development. However, this does not provide a complete answer, and more information about the deleted genes and their mechanisms remains to be discovered. Other genes, or some form of interplay among genes, may be the cause of other anomalies associated with the syndrome.
In approximately 90 per cent of the cases, 22q11 deletion syndrome is caused by a new mutation, meaning that the mutated gene has not been inherited and is not present in the affected individual’s family. There is no increased risk that parents of a child with a new mutation will have another child with the syndrome.
In around 10 per cent of the cases, the syndrome is passed down by autosomal dominant inheritance. This means that if one of the parents has the chromosome deletion, the risk of passing it down to sons or daughters is 50 per cent. It is impossible, however, to predict if an affected child’s symptoms will be severe or very mild. Children who do not inherit the chromosome deletion will neither have the syndrome nor run the risk of passing it down.
Every individual with the 22q11 deletion syndrome has a unique disorder. The number of symptoms and their severity will vary, even when the deletion causing the syndrome appears to be practically identical. A parent with very mild symptoms, who may not even know that he or she has a chromosome deletion, may have a child with far more severe symptoms. The reverse situation can also arise.
Many different organ systems may be affected. The most commonly occurring symptoms include congenital heart defects, cleft palate and weakness in the roof of the mouth, increased susceptibility to infections, and symptoms from the nervous system which often cause delayed development, mild to moderate learning difficulties, and neuropsychiatric problems.
Symptoms also vary at different ages. Cardiac defects, feeding difficulties, frequent infections, and speech problems dominate for younger children, while learning difficulties and neuropsychiatric problems become apparent later. Certain mild facial characteristics are common, with a broad nose and a rounded nose tip, widely spaced eyes with narrow eyelids, small mouth and chin, flat cheekbones, and round low-set ears. Persons with the syndrome often also have long tapered fingers.
Heart defects are often found in the outflow tracts of the heart. More than half of the children with this syndrome have congenital heart defects. There may be many different kinds of cardiac defects, ranging from mild to more severe. Examples of the most common heart defects are interrupted aortic arch, narrowing of the pulmonary artery (pulmonalis stenosis), total blockage of the pulmonary artery (pulmonalis atresis), remaining common stem extending from the heart to the aorta and the pulmonary artery (truncus), or a hole in the wall separating the lower chambers of the heart (VSD, ventricle septum defect) and a combination defect including, among other things, constriction of the outflow to the pulmonary artery and a hole in the wall separating the lower chambers of the heart (Tetralogy of Fallot). All these heart defects generally present with symptoms early, often during the first few days or weeks of life.
Cleft palate and poor palate function both occur frequently. The most common types are isolated cleft palate or submucosal cleft palate, which is not visible to the naked eye. Very seldom there may be complete lip, jaw, and palate clefting. Irrespective of whether or not the palate is cleft, most people with the syndrome also have poor palate function (Velo Pharyngeal Insufficiency = VPI). This means that the roof of the mouth (the palate) does not properly close off the oral cavity from the nasal cavity, as it normally should to permit speech and swallowing. When the roof of a newborn infant’s mouth is malformed, the infant will often find it difficult to suck, and milk will often come out of the child’s nose. Later in life, VPI mainly leads to slurred pronunciation and often to very open, nasal speech owing to leakage of air up into the nose.
Feeding difficulties are frequent. It is difficult for these infants to suck, and they often vomit their food through the nose. These feeding difficulties are mainly caused by poor palate function, but may also be attributable to cardiac weakness or disturbed motor development in the gastrointestinal tract. Somewhat older children may have difficulties becoming accustomed to solid foods.
The teeth may have poorly mineralised enamel and can erupt late. Sometimes certain teeth never erupt at all. Some individuals with the syndrome have problems with severe caries (dental decay) and gum infections.
Immune system problems of different kinds are common, although only a few children will have serious immunodeficiencies. The immunodeficiency is caused by underdevelopment of the thymus. The thymus is formed during the fetal period, and is located at the top of the throat in front of the oesophagus, to migrate later down to the upper chest cavity. The function of the thymus is to serve as a kind of ”school” for a certain kind of white blood cells known as T-lymphocytes. They protect the body, primarily against viral infections. They also play a regulatory, coordinating function in the human immune system.
If the thymus is missing or is seriously underdeveloped, the T-lymphocytes will not mature and the child will be born with a severe immunodeficiency and the risk of developing life-threatening infections. This is, however, a relatively infrequent occurrence in the 22q11 deletion syndrome. It is more common for the thymus to be small at birth, and not to have migrated down to its proper place in the chest cavity. This leads to a minor immunodeficiency that mainly appears as increased vulnerability to infections, with upper respiratory tract infections and ear infections being the most common.
In the majority of individuals this increased susceptibility to infections is spontaneously rectified, and is more or less normalised during the course of the child’s preschool and school years. However, the immunodeficiency can last into adult life, with an increased risk of autoimmune diseases, in which the immune defence system of the body attacks its own cells.
Hypocalcaemia is caused by underdeveloped or, in rare cases, absent parathyroid glands. In either case there is too little of the hormone normally produced by these glands, PTH (parathyroid hormone). PTH is important in regulating the calcium metabolism. Symptoms of low calcium levels usually appear during infancy as more pronounced trembling than is normally seen in newborns. The body needs a great deal of PTH in early life, but less thereafter, so the calcium deficiency is often spontaneously corrected later in life. It may remain a latent problem, however, recurring in situations in which the body is subjected to stress, for example in connection with surgery.
Low calcium levels can also give symptoms such as muscle cramps, fainting, or epileptic seizures. Other, more diffuse symptoms may also occur, including muscular weakness, numbness, prickling sensations, anxiety, and sleeping problems. Aching legs, often interpreted as growing pains, may be attributable to low blood calcium levels. It is difficult to determine with certainty if calcium deficiencies remain common in older children and adults.
Short stature is common. Sometimes the growth disturbance is caused by a treatable condition, such as thyroid deficiency, hypersensitivity to gluten, or growth hormone deficiency. Growth hormone treatment is given only when the deficiency has been confirmed.
Psychological and motor development are somewhat delayed in many of these children. This applies particularly to speech and language acquisition. Many children with the syndrome do not begin to speak until the age of two or three, and some even later. Delayed speech development may remain in older children as well, in the form of language difficulties, and a tendency to speak in short, simple sentences. Many individuals with the syndrome have limited facial expression, which can make communication more difficult. However, in spite of this delayed speech development, many individuals with 22q11 deletion syndrome turn out to be strongest in the verbal area once they begin school.
Abnormalities of motor control are common. For some individuals the main problem is gross motor development (balance, running, jumping, muscular strength), while others primarily have problems in terms of fine motor development (finger skills, hand-eye control). Most of these children have slight problems with both.
Intellectual development is also affected in most cases. Studies carried out to date indicate that nearly half the children with the syndrome have mild intellectual disability. There also appears to be a tendency for children whose intellectual development is within the normal range to be lower than average. Their intellectual profiles are often uneven, with functions controlled by the right hemisphere of the brain, such as sense of form and visual perception (the ability of the brain to receive and interpret signals from the eye) often being less well developed than language skills, which tend to be controlled by the left hemisphere.
Neuropsychiatric problems are common. These include attention deficits and difficulties with social interaction. Many of these children are diagnosed as suffering from ADHD (attention deficit hyperactivity disorder). Their psychological energy level is often low, which may result in concentration and attention difficulties, as well as decreased endurance. Children with the syndrome who have specific problems with social interaction may have some form of autistic spectrum disorder. Only in a very small number of children, however, are these symptoms so pronounced that the child may be diagnosed with autistic syndrome.
Learning difficulties are frequent. The combination of poor intellectual level, sometimes with mental retardation, as well as concentration, endurance, and visual perception difficulties, means that most children with the syndrome need extra support at school, and some form of special education. The learning difficulties become more pronounced with age as educational demands increase.
Psychiatric symptoms of different kinds have been described as frequently found in adults with 22q11 deletion syndrome. Anxiety and depressive states are most common, as well as manic depression (bipolar affective disorder). Schizophrenia and schizophrenic states are probably also more common than in the general population.
Eye problems, such as impaired vision, severe astigmatism, and squinting are also frequent.
Ear problems, including ear infections, fluids in the middle ear, and problems with wax in the auditory canals are common. Many of these children have slightly impaired hearing, and a small number have more severe hearing deficiencies.
Other malformations and aberrations may also be seen, but less frequently. These include malformations of the urinary tract, the feet (club foot), the skeleton, and the gastrointestinal tract. Scoliosis (curvature of the spine) is also found more frequently than in the general population.
The deletion on chromosome 22 can be detected through blood tests using FISH analysis (fluorescent in situ hybridisation) and should always be done when there is reason to suspect that an individual might have the syndrome. The deletion can also be detected by MLPA analysis (Multiplex Ligation-dependent Probe Amplification). Ordinary chromosome analysis on cultured blood cells seldom reveals the deletion, although such tests may be considered in order to test for other chromosomal aberrations.
Since so many different symptoms can be involved in the 22q11 deletion syndrome, it is essential that treatment is coordinated by a multidisciplinary team with experience of the syndrome, who can be attentive to the variety of problems that may arise.
Cardiac assessment is important. Children with complex heart defects need to be examined by a paediatric cardiologist and, when necessary, referred for surgery. Sometimes operations have to be carried out stepwise on separate occasions. The hospitals in Sweden where such surgery can be performed today are in Gothenburg and Lund. For the majority of children with heart defects, the prognosis is good.
Because many of the children with the syndrome have eating difficulties, it is important to consult a dietician and a speech therapist. Some young children may need to be tube fed through a naseo-gastric tube for a period of time.
The immune system must always be investigated. This is done through blood test analysis. Children who suffer from frequent infections may need preventive antibiotic treatment for shorter or longer periods of time. Treatment with supplementary gammaglobulin (antibodies) may sometimes be used to reduce vulnerability to infection. Children and adults with pronounced immune deficiencies will require particular caution in treatment. For example, they should not be vaccinated with live vaccines. If they should require blood transfusions, the blood and plasma products should be radiated. In some very rare cases, the immune deficiency may be so severe as to result in life-threatening infections. During follow ups of patients with 22q11 deletion syndrome, it should always be noted whether they have a tendency to acquire repeated infections.
The function of the parathyroid glands should be tested using blood samples. When there are both insufficient function of the glands and symptoms, medical treatment can be given.
Thyroid function should be monitored as well, as there is an increased risk of hypothyroidism.
Growth hormone treatment is given when a growth hormone deficiency has been confirmed. This treatment requires daily injections. Treatment may even be needed at adult ages if there is a pronounced growth hormone deficiency, because growth hormone not only affects growth but is also an important regulator of the metabolism.
Vision and hearing should also be checked early. Some children will require glasses, and children with severe hearing impairments will need hearing aids.
A specialist in paediatric dentistry should examine children with 22q11 deletion syndrome at an early age. If the syndrome is discovered in adulthood, an examination can be made by a hospital dentist or at an oral medicine clinic. Most of the affected individuals will need supplementary dental care, including fluoride treatments and assistance with their dental hygiene. Between the ages of seven to nine there should be a thorough dental and orthodontic examination. For children with congenital heart defects, antibiotic treatment should always be considered in conjunction with dental interventions, owing to the risk of cardiac infections caused by buccal bacteria entering the bloodstream.
Special attention must be paid to speech and language development. When speech and language development are delayed, it is essential that a speech therapist is contacted at an early stage, to examine the child and provide treatment. Palate function should be assessed by both a speech therapist and a physician specializing in voice and speech development (a phoniatrician). If the child has a cleft palate, treatment is coordinated by a cleft lip and palate treatment team, and surgery is performed by a specialist plastic surgeon. Many children with defective palates may require pharyngeal flap surgery. This surgery, in combination with speech therapy, may improve palate function and thus speech.
It is usually helpful for the family to be put into early contact with a multidisciplinary rehabilitation team. The treatment required will be determined in relation to the degree and scope of the disability. The team often includes professionals from various categories, all of whom can provide different kinds of support. Some children may need to see a physiotherapist for evaluation and consultation regarding a suitable exercise program. The general development of the child must be followed, and there should also be an assessment by a psychologist.
For most children with the syndrome, a more extensive neuropsychiatric assessment, including a neuropsychological examination and follow up, will be needed.
At school, most children with the syndrome will require a great deal of help in terms of special education and individual programmes. Information and planning in good time before the child is to begin school are important. The educational methods will have to be adapted to the abilities and intellectual level of each child. Good school support is important for children and young people with 22q11 deletion syndrome, both in terms of classroom learning and peer interaction.
Some adults with the syndrome may continue to need support from a multidisciplinary team. Many of them will need to be in contact with adult psychiatry units.
It is important to consider the entire family’s need for psychological and social support. The health care services or the multidisciplinary team can help the family establish contact with a counsellor or a psychologist. Rehabilitation counsellors can also provide families with information as to what social services are available.
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Specialist team for diagnostics, examination and treatment:
In Sweden there are two specialist teams, one in Gothenburg and one in Stockholm. The teams include a paediatrician, an audiologist, an endocrinologist, a phoniatrician, a geneticist, a cardiologist, a speech therapist, a neuropsychiatrist, a plastic surgeon, a dentist, a psychologist, an ophthalmologist, and an otologist.
Liaison officer for the team in Gothenburg is senior physician Sólveig Óskarsdóttir, Section for paediatric immunology, The Queen Silvia Children’s Hospital, SE-416 85 Gothenburg, Sweden. Tel +46 31 343 40 00.
Liaison officer for the team in Stockholm is senior physician Britt-Marie Anderlid, Astrid Lindgren Children’s Hospital and the Department of Clinical Genetics, Karolinska University Hospital, Solna, SE-171 76 Stockholm, Sweden. Tel +46 8 517 700 00.
FISH- and MLPA-diagnostics:
Diagnostic tests can be carried out at regional departments of clinical genetics.
There is special expertise on orofacial problems (problems of the mouth and facial region) available at the Mun-H-Center, Department of Odontology in Gothenburg. Address: Mun-H-Center, Odontologen, Medicinaregatan 12A, SE-413 90 Gothenburg, Sweden. Tel +46 31 750 92 00, fax +46 31 750 92 01, email: mun-h-center@vgregion.se, Internet: www.mun-h-center.se.
Senior physician Sólveig Óskarsdóttir, The Queen Silvia Children’s Hospital, SE-416 85 Gothenburg, Sweden. Tel +46 31 343 40 00, fax +46 31 707 06 94, email: solveig.oskarsdottir@vgregion.se.
Senior physician Vanda Friman, Department of Infectious Diseases, Sahlgrenska University Hospital/Östra, SE-416 85 Gothenburg, Sweden. Tel +46 31 343 40 00.
Senior physician Britt-Marie Anderlid, Astrid Lindgren Children’s Hospital, Karolinska University Hospital, Solna, SE-171 76 Stockholm, Sweden. Tel +46 8 517 700 00.
Assistant Professor Elisabeth Blennow, Department of Clinical Genetics, Karolinska University Hospital, Solna, SE-171 76 Stockholm, Sweden. Tel +46 8 517 753 80, fax +46 8 32 77 34.
Professor Christopher Gillberg, Neuropsychologist Lena Niklasson, Assistant Professor Peder Rasmussen, Division of Neurology, Neuropsychiatry, and Rehabilitation, The Queen Silvia Children’s Hospital, Box 171 13, SE-402 61 Gothenburg, Sweden. Tel +46 31 343 40 00.
Speech therapist Christina Persson, Speech Therapy and Phoniatrics Clinic, Sahlgrenska University Hospital, SE-413 45 Gothenburg, Sweden. Tel +46 31 342 10 00.
The Ågrenska Centre arranges stays for children and young people with disabilities and their families, and it is particularly attentive to the needs of people with rare diseases. The Centre is located on the outskirts of Gothenburg, and is open to families from all over Sweden. For information, please contact the Ågrenska Centre, Box 2058, SE-436 02 Hovås, Sweden. Tel +46 31 750 91 00, fax +46 31 91 19 79, email: agrenska@agrenska.se, Internet: www.agrenska.se.
The Swedish 22q11 deletion syndrome association, c/o RoseMarie Larsson, Norgårdsvägen 17, SE-430 90 Öckerö, Sweden. Email: r-marie@telia.com, Internet: www.22q11.se.
Rare Diseases Sweden, Box 1386, SE-172 27 Sundbyberg, Sweden. Tel: +46 8 764 49 99, email: info@sallsyntadiagnoser.se, www.sallsyntadiagnoser.se. Rare Diseases Sweden is a federation of rare disease organizations, serving the interests of people with rare disorders.
A Swedish association for children with cardiac defects: Hjärtebarnsförbundet, Kammakaregatan 47, SE-111 24 Stockholm, Sweden. Tel +46 8 442 46 50, e-mail: kansliet@hjartebarn.org, Internet: www.hjartebarn.org
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Research is being pursued in Gothenburg, Sweden, both at The Queen Silvia Children’s Hospital, The Sahlgrenska University Hospital, and at Mun-H-Center (see under the heading “National and regional resources”). There is also extensive research being carried on internationally.
An information booklet on 22q11 deletion syndrome, which summarises the information in this database text, is available free of charge from the Publications Department of the Swedish National Board of Health and Welfare, (in Swedish only, article number 1998-126-1080). Address: SE-106 30 Stockholm, Sweden. Fax: +46 35 19 75 29, email: publikationsservice@socialstyrelsen.se, or tel: +46 75 247 38 80. Postage will be charged for bulk orders.
Newsletter (in Swedish only) from Ågrenska, no. 200 (2002). Order from: Ågrenska, Box 2058, SE-436 02 Hovås, Sweden. Tel +46 31 750 91 00, fax +46 31 91 19 79. The newsletter is also available at www.agrenska.se.
22q and You, a quarterly on-line journal for laypeople and professionals. Internet: www.cbil.upenn.edu/VCFS.
Velo-Cardio-Facial Syndrome Educational Foundation. Internet: www.vcfsef.org.
The Jeffrey Modell Foundation, an American patient association for immune defence diseases, offers information on the syndrome. Internet: www.jmfworld.com.
Cohen E, Chow EW, Weksberg R, Bassett AS. Phenotype of adults with the 22q11 deletion syndrome: A review. Am J Med Genet 1999; 86: 359-365.
Eicher PS, McDonald-Mcginn DM, Fox CA, Driscoll DA, Emanuel BS, Zackai EH. Dysphagia in children with a 22q11.2 deletion: unusual pattern found on modified barium swallow. J Pediatr 2000; 137: 158-164.
Hieronimus S, Bec-Roche M, Pedeutour F, Lamber JC, Wagner-Malher K, Mas JC et al. The spectrum of parathyroid gland dysfunction associated with the microdeletion 22q11. Eur J Endocrinol 2006; 155: 47-52.
Klingberg G, Óskarsdóttir S, Johannesson EL, Noren JG. Oral manifestations in 22q11 deletion syndrome. Int J Paediatr Dent 2002; 12: 14-23.
Klingberg G, Dietz W, Óskarsdóttir S, Odelius H, Gelander L, Noren JG. Morphological appearance and chemical composition of enamel in primary teeth from patients with 22q11 deletion syndrome. Eur J Oral Sci 2005; 113: 303-311.
Klingberg G, Dietz W, Óskarsdóttir S, Friman V, Bohman E, Carlén A. Caries-related saliva properties in individuals with 22q11 deletion syndrome. Oral Surg Oral Med Oral Patol Oral Radio Endod 2006, in press.
McDonald-McGinn DM, Kirschner R, Goldmuntz E, Sullivan K, Eicher P, Gerdes M et al. The Philadelphia story: the 22q11.2 deletion syndrome: report on 250 patients. Genet Couns 1999; 10: 11-24.
Niklasson L, Rasmussen P, Óskarsdóttir S, Gillberg C. Chromosome 22q11 deletion syndrome (CATCH 22): neuropsychiatric and neuropsychological aspects. Dev Med Child Neurol 2002; 44: 44-50.
Niklasson L, Rasmussen P, Óskarsdóttir S, Gillberg C. Attention deficits in children with 22q.11 deletion syndrome. Dev Med Child Neurol 2005; 47: 803-807.
Óskarsdóttir S, Vujic M, Fasth A. Incidence and prevalence of the 22q11 deletion syndrome: a population-based study in western Sweden. Arch Dis Child 2004; 89: 148-151.
Óskarsdóttir S, Persson C, Eriksson BO, Fasth A. Presenting phenotype in 100 children with 22q11 deletion syndrome. Eur J Pediar 2005; 164: 146-153.
Óskarsdóttir S, Belfrage M, Sandstedt E, Viggedal G, Uvebrant P. Disabilities and cognition in children and adolescents with 22q11 deletion syndrome. Dev Med Child Neurol 2005; 47: 177-184.
Óskarsdóttir S, Fasth A, Belfrage M, Viggedal G, Persson C, Eriksson BO. CATCH 22-syndrom/22q11-deletionssyndrom: Underdiagnosticerad missförstådd sjukdomsgrupp med skiftande klinisk bild. Läkartidningen 1999; 96: 4789-4793.
Óskarsdóttir S, Fasth A, Niklasson L, Rasmussen P, Gillberg C. 22q11-deletion (CATCH 22) - förbisedd orsak till medicinska problem i kombination med neuropsykiatriska funktionshinder. Socialmedicinsk tidskrift 2001; 78: häfte 2.
Persson C, Lohmander A, Jonsson R, Óskarsdóttir S, Söderpalm E. A prospective cross-sectional study of speech in patients with the 22q11 deletion syndrome. J Commun Disord 2003; 36: 13-47.
Persson C, Niklasson L, Óskarsdóttir S, Johansson S, Jonsson R, Söderpalm E. Language skills in 5-8-year-old children with 22q11 deletion syndrome. Int J Lang Commun Disord 2006; 41: 313-33.
Sullivan KE. The clinical, immunological and molecular spectrum of chromosome 22q11.2 deletion syndrome and DiGeorge syndrome. Curr Opin Allergy Clin Immunol 2004; 4: 505-512.
Swillen A, Vogels A, Devriendt K, Fryns JP. Chromosome 22q11 deletion syndrome: update and review of the clinical features, cognitive-behavioural spectrum, and psychiatric complications. Am J Med Genet 2000; 97: 128-135.
Vantrappen G, Rommel N, Swillen A, Cremers CW, Fryns JP, Devriendt K. Velo-cardio-facial syndrome: guidelines for diagnosis, treatment and follow-up of ENT manifestations. Acta Otorhinolaryngol Belg 2003; 57: 1-106.
OMIM (Online Mendelian Inheritance in Man).
Internet: www.ncbi.nlm.nih.gov/omim.
search: digeorge syndrome
GeneReviews (University of Washington)
Internet: www.genetests.org (select Genereviews).
search: 22q11.2 deletion syndrome
Velo-Cardio-Facial Syndrome Educational Foundation (VCFS) is an organisation for laypeople and professionals, the aim of which is to circulate information on the syndrome. Internet: www.vcfsef.org.
The Swedish Information Centre for Rare Diseases produced and edited this information material.
The medical expert who wrote the draft of this information material is senior physician Sólveig Óskarsdóttir, The Queen Silvia Children’s Hospital, Gothenburg, Sweden.
The relevant organisations for the disabled/patient associations have been given the opportunity to comment on the content of the text.
An expert group on rare diseases, affiliated with the University of Gothenburg, approved the material prior to publication.
Date of publication: 2009-02-26
Version: 2.2
Publication date of the Swedish version: 2007-07-02
For enquiries contact The Swedish Information Centre for Rare Diseases, The Sahlgrenska Academy at the University of Gothenburg, Box 400, SE-405 30 Gothenburg, Sweden, tel: +46 31 786 55 90, email: ovanligadiagnoser@gu.se.