Find information on thousands of medical conditions and prescription drugs.

Chromosome 22, microdeletion 22 q11

22q11.2 deletion syndrome (also called DiGeorge syndrome and velocardiofacial syndrome) is a disorder caused by the deletion of a small piece of chromosome 22. The deletion occurs near the middle of the chromosome at a location designated q11.2. more...

Home
Diseases
A
B
C
Angioedema
C syndrome
Cacophobia
Café au lait spot
Calcinosis cutis
Calculi
Campylobacter
Canavan leukodystrophy
Cancer
Candidiasis
Canga's bead symptom
Canine distemper
Carcinoid syndrome
Carcinoma, squamous cell
Carcinophobia
Cardiac arrest
Cardiofaciocutaneous...
Cardiomyopathy
Cardiophobia
Cardiospasm
Carnitine transporter...
Carnitine-acylcarnitine...
Caroli disease
Carotenemia
Carpal tunnel syndrome
Carpenter syndrome
Cartilage-hair hypoplasia
Castleman's disease
Cat-scratch disease
CATCH 22 syndrome
Causalgia
Cayler syndrome
CCHS
CDG syndrome
CDG syndrome type 1A
Celiac sprue
Cenani Lenz syndactylism
Ceramidase deficiency
Cerebellar ataxia
Cerebellar hypoplasia
Cerebral amyloid angiopathy
Cerebral aneurysm
Cerebral cavernous...
Cerebral gigantism
Cerebral palsy
Cerebral thrombosis
Ceroid lipofuscinois,...
Cervical cancer
Chagas disease
Chalazion
Chancroid
Charcot disease
Charcot-Marie-Tooth disease
CHARGE Association
Chediak-Higashi syndrome
Chemodectoma
Cherubism
Chickenpox
Chikungunya
Childhood disintegrative...
Chionophobia
Chlamydia
Chlamydia trachomatis
Cholangiocarcinoma
Cholecystitis
Cholelithiasis
Cholera
Cholestasis
Cholesterol pneumonia
Chondrocalcinosis
Chondrodystrophy
Chondromalacia
Chondrosarcoma
Chorea (disease)
Chorea acanthocytosis
Choriocarcinoma
Chorioretinitis
Choroid plexus cyst
Christmas disease
Chromhidrosis
Chromophobia
Chromosome 15q, partial...
Chromosome 15q, trisomy
Chromosome 22,...
Chronic fatigue immune...
Chronic fatigue syndrome
Chronic granulomatous...
Chronic lymphocytic leukemia
Chronic myelogenous leukemia
Chronic obstructive...
Chronic renal failure
Churg-Strauss syndrome
Ciguatera fish poisoning
Cinchonism
Citrullinemia
Cleft lip
Cleft palate
Climacophobia
Clinophobia
Cloacal exstrophy
Clubfoot
Cluster headache
Coccidioidomycosis
Cockayne's syndrome
Coffin-Lowry syndrome
Colitis
Color blindness
Colorado tick fever
Combined hyperlipidemia,...
Common cold
Common variable...
Compartment syndrome
Conductive hearing loss
Condyloma
Condyloma acuminatum
Cone dystrophy
Congenital adrenal...
Congenital afibrinogenemia
Congenital diaphragmatic...
Congenital erythropoietic...
Congenital facial diplegia
Congenital hypothyroidism
Congenital ichthyosis
Congenital syphilis
Congenital toxoplasmosis
Congestive heart disease
Conjunctivitis
Conn's syndrome
Constitutional growth delay
Conversion disorder
Coprophobia
Coproporhyria
Cor pulmonale
Cor triatriatum
Cornelia de Lange syndrome
Coronary heart disease
Cortical dysplasia
Corticobasal degeneration
Costello syndrome
Costochondritis
Cowpox
Craniodiaphyseal dysplasia
Craniofacial dysostosis
Craniostenosis
Craniosynostosis
CREST syndrome
Cretinism
Creutzfeldt-Jakob disease
Cri du chat
Cri du chat
Crohn's disease
Croup
Crouzon syndrome
Crouzonodermoskeletal...
Crow-Fukase syndrome
Cryoglobulinemia
Cryophobia
Cryptococcosis
Crystallophobia
Cushing's syndrome
Cutaneous larva migrans
Cutis verticis gyrata
Cyclic neutropenia
Cyclic vomiting syndrome
Cystic fibrosis
Cystinosis
Cystinuria
Cytomegalovirus
Dilated cardiomyopathy
Hypertrophic cardiomyopathy
Restrictive cardiomyopathy
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
Medicines

The features of this syndrome vary widely, even among members of the same family, and affect many parts of the body. Characteristic signs and symptoms include heart defects that are often present from birth, an opening in the roof of the mouth (a cleft palate or other defect in the palate), learning disabilities, recurrent infections caused by problems with the immune system, and mild differences in facial features. Affected individuals may also have kidney abnormalities, low levels of calcium in the blood (which can result in seizures), significant feeding difficulties, autoimmune disorders such as rheumatoid arthritis, and an increased risk of developing mental illnesses such as schizophrenia and bipolar disorder.

Because the signs and symptoms of 22q11.2 deletion syndrome are so varied, different groupings of features were once described as separate conditions. Doctors named these conditions DiGeorge syndrome, velocardiofacial syndrome (also called Shprintzen syndrome), and conotruncal anomaly face syndrome. In addition, some children with the 22q11.2 deletion were diagnosed with Opitz G/BBB syndrome and Cayler cardiofacial syndrome. Once the genetic basis for these disorders was identified, doctors determined that they were all part of a single syndrome with many possible signs and symptoms. To avoid confusion, this condition is usually called 22q11.2 deletion syndrome, a description based on its underlying genetic cause.

Symptoms

Individuals with a 22q11 deletion have a range of findings, including:

  • Congenital heart disease (74% of individuals), particularly conotruncal malformations (tetralogy of Fallot, interrupted aortic arch, ventricular septal defect, and truncus arteriosus)
  • palatal abnormalities (69%), particularly velopharyngeal incompetence (VPI), submucosal cleft palate, and cleft palate; characteristic facial features (present in the majority of Caucasian individuals)
  • learning difficulties (70-90%)
  • an immune deficiency regardless of their clinical presentation (77%)
  • hypocalcemia (50%)
  • significant feeding problems (30%)
  • renal anomalies (37%)
  • hearing loss (both conductive and sensorineural)
  • laryngotracheoesophageal anomalies
  • growth hormone deficiency
  • autoimmune disorders
  • seizures (without hypocalcemia)
  • skeletal abnormalities

Thymus, parathyroid glands and heart derive from the same primitive embryonic structure and that is why these three organs are dysfunctioned together in this disease. Affected patients (usually children) are prone to yeast infections.

Cause

The disease is related with genetic deletions (loss of a small part of the genetic material) found on the long arm of the 22nd chromosome. Some patients with similar clinical features may have deletions on the short arm of chromosome 10.

Read more at Wikipedia.org


[List your site here Free!]


Disruption of Gene Interaction Linked to Schizophrenia
From PR Newswire, 12/1/05

Studies of PRODH deficiency demonstrate COMT compensates for overactive dopamine signaling, according to St. Jude

MEMPHIS, Tenn., Dec. 1 /PRNewswire/ -- The loss of the genes PRODH and COMT contributes directly to major symptoms of schizophrenia by upsetting the balance of the brain chemicals glutamate and dopamine, according to a group of investigators that includes a scientist now at St. Jude Children's Research Hospital.

A mutation that eliminates PRODH causes an abnormal rise in the levels of both of these chemicals; the additional loss of COMT blocks the brain's ability to compensate for this imbalance. This finding offers new insights into the genetic basis of schizophrenia, the researchers said.

Schizophrenia is a mental disorder usually characterized by loss of touch with reality; illogical thinking; hallucinations; and other abnormal emotional, behavioral or intellectual disturbances. The investigators developed a model of schizophrenia that provides a way to study and understand how the loss of PRODH and COMT gene activity contributes to schizophrenia symptoms.

The new insights are important because the loss of the PRODH gene causes the imbalance in the levels of both glutamate and dopamine; this imbalance contributes directly to the symptoms of schizophrenia, according to Stanislav Zakharenko, M.D., Ph.D., an assistant member of the Department of Developmental Neurobiology at St. Jude.

The team investigated the roles of PRODH and COMT because these genes are located in the q11 region of human chromosome 22. Previous work by other scientists had showed that a mutation in this region -- the 22q11 microdeletion -- is an important risk factor for developing schizophrenia.

The study's findings linked changes seen at the molecular level directly to symptoms of schizophrenia seen in humans, said Zakharenko, who is a co- author of a report on this work that appears in the November 15 issue of Nature Neuroscience. The work was completed by Zakharenko and his colleagues at Columbia University (New York), Rockefeller University (New York) and the University of Utrecht (the Netherlands). Zakharenko is continuing his work on the molecular causes of schizophrenia at St. Jude.

The key finding in the current study was that the models of PRODH deficiency had increased COMT activity in the frontal cortex of the brain. "This might reflect a response to the increased dopamine activity caused by PRODH deficiency," Zakharenko said. "And it shows that when PRODH is lost, the additional loss of COMT due to the 22q11 mutation may worsen the symptoms of schizophrenia by allowing dopamine levels to rise."

The study also showed why patients with schizophrenia who also have the 22q11 microdeletion are especially disadvantaged. "COMT upregulation appears to be a response that brings the level of dopamine signaling back to normal," Zakharenko said. "So patients with the 22q11 microdeletion are unable to compensate for their PRODH deficiency by upregulating COMT."

In the same issue of Nature Neuroscience, another group of investigators reports that their study of adolescents with the 22q11 deletion showed that low activity of COMT is a risk factor for loss of volume of the prefrontal cortex; and that this same mutation also puts adolescents at risk for developing psychotic symptoms.

Other authors of the study include Joseph A. Gogos, Maria Karayiorgou, Marta Paterlini, Wen-Sung Lai, Jie Qin, Hui Zhang, Jun Mukai, David Sulzer, Paul Pavlidis and Steven A. Siegelbaum (Columbia University and Rockefeller University) and Koen G.C. Westphal and Berend Olivier (University of Utrecht).

St. Jude Children's Research Hospital

St. Jude Children's Research Hospital is internationally recognized for its pioneering work in finding cures and saving children with cancer and other catastrophic diseases. Founded by late entertainer Danny Thomas and based in Memphis, Tennessee, St. Jude freely shares its discoveries with scientific and medical communities around the world. No family ever pays for treatments not covered by insurance, and families without insurance are never asked to pay. St. Jude is financially supported by ALSAC, its fundraising organization. For more information, please visit http://www.stjude.org/.

CONTACT: Carrie Strehlau of St. Jude Public Relations, +1-901-495-2295, or carrie.strehlau@stjude.org, or Marc Kusinitz of St. Jude Scientific Communications, +1-901-495-5020, or marc.kusinitz@stjude.org

Web site: http://www.stjude.org/

COPYRIGHT 2005 PR Newswire Association LLC
COPYRIGHT 2005 Gale Group

Return to Chromosome 22, microdeletion 22 q11
Home Contact Resources Exchange Links ebay