51
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Marino B, Digilio M, Toscano A. Common arterial trunk, DiGeorge syndrome and microdeletion 22q11. PROGRESS IN PEDIATRIC CARDIOLOGY 2002. [DOI: 10.1016/s1058-9813(02)00004-8] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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52
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Volpe P, Gentile M, Marasini M. Interrupted aortic arch type A with 22q11 deletion: prenatal detection of an unusual association. Prenat Diagn 2002; 22:371-4. [PMID: 12001189 DOI: 10.1002/pd.320] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Interrupted aortic arch is a rare, severe congenital heart defect subdivided into three types, A, B and C, according to the site of interruption. Type C is by far the least common form of interrupted aortic arch (less than 5% of cases), type A is commonly an isolated defect whereas type B is frequently associated with 22q11 deletion. Differentiation of interrupted aortic arch type A from type B by prenatal echocardiography is possible but difficult; it needs to be done on the basis of observation of reliable morphological indicators which point to the correct diagnosis. Here we report the first case of prenatal diagnosis of interrupted aortic arch type A associated with 22q11 deletion. The significance of this association is not yet clear, since 22q11 genes mainly affect embryonic cardiovascular morphogenesis of those regions whose development is critically dependent on neural crest cell migration and function, affected in type B defect but not in type A.
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Affiliation(s)
- P Volpe
- Department of Obstetrics and Gynecology, Hospital Di Venere-Giovanni XXIII, Bari, Italy
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53
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Rauch R, Rauch A, Koch A, Kumpf M, Dufke A, Singer H, Hofbeck M. Cervical origin of the subclavian artery as a specific marker for monosomy 22q11. Am J Cardiol 2002; 89:481-4. [PMID: 11835939 DOI: 10.1016/s0002-9149(01)02279-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- Ralf Rauch
- Department of Cardiology, University Children's Hospital, Tuebingen, Germany.
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54
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McElhinney DB, Clark BJ, Weinberg PM, Kenton ML, McDonald-McGinn D, Driscoll DA, Zackai EH, Goldmuntz E. Association of chromosome 22q11 deletion with isolated anomalies of aortic arch laterality and branching. J Am Coll Cardiol 2001; 37:2114-9. [PMID: 11419896 DOI: 10.1016/s0735-1097(01)01286-4] [Citation(s) in RCA: 199] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
OBJECTIVES The purpose of this study was to determine the frequency of chromosome 22q11 deletions in patients with isolated anomalies of the aortic arch and its branches. BACKGROUND Chromosome 22q11 deletions are often present in patients with certain forms of congenital cardiovascular disease, including tetralogy of Fallot, truncus arteriosus and interruption of the aortic arch. Among patients with these anomalies, chromosome 22q11 deletion is more common in those with abnormal aortic arch laterality or branching. METHODS We studied 66 patients with isolated anomalies of the aortic arch and no associated intracardiac defects for deletions within chromosome 22q11, using fluorescence in situ hybridization with the cosmid probe N25 (D22S75). Arch anomalies included: double aortic arch (n = 22); right aortic arch with aberrant left subclavian artery (n = 28); right aortic arch with mirror-image branching and a vascular ring formed by a left-sided ductus from the descending aorta (n = 5); right aortic arch with mirror-image branching and no vascular ring (n = 4); and left aortic arch with aberrant right subclavian artery (n = 7). In addition, four patients had a cervical aortic arch, four had aortic coarctation and six had hypoplasia/atresia of the proximal pulmonary arteries. RESULTS Chromosome 22q11 deletions were found in 16 patients (24%) across the full spectrum of anomalies studied. Among the morphologic variables analyzed, only hypoplasia/atresia of the proximal pulmonary arteries correlated with the deletion (p = 0.03). Among patients with a double arch, the frequency of chromosome 22q11 deletion was higher in those with an atretic minor arch than it was in those with a patent minor arch (p = 0.02). CONCLUSIONS Chromosome 22q11 deletion is associated with isolated anomalies of laterality or branching of the aortic arch in 24% of cases in our series. These findings should alert the clinician to consider deletion screening in patients with isolated anomalies of the aortic arch.
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Affiliation(s)
- D B McElhinney
- Division of Pediatric Cardiology, Children's Hospital of Philadelphia, Pennsylvania 19104, USA
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55
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Boudjemline Y, Fermont L, Le Bidois J, Lyonnet S, Sidi D, Bonnet D. Prevalence of 22q11 deletion in fetuses with conotruncal cardiac defects: a 6-year prospective study. J Pediatr 2001; 138:520-4. [PMID: 11295715 DOI: 10.1067/mpd.2001.112174] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVES Conotruncal malformations (CTMs) are a major feature of 22q11 microdeletion (22qdel). The prevalence of 22qdel in fetuses harboring these defects is unknown. We assessed the prevalence of 22qdel in a population of fetuses with conotruncal cardiac defects. STUDY DESIGN Consecutive fetuses (n = 261) with a CTM and a normal karyotype were included in the study. All fetuses were screened for 22qdel by means of fluorescent in situ hybridization. RESULTS A 22qdel was found in 54 fetuses (20.7%). The proportion of 22qdel for each CTM was: tetralogy of Fallot (14/100), pulmonary atresia with ventricular septal defect (11/61), tetralogy of Fallot with absent pulmonary valves (6/16), interrupted aortic arch (10/22), truncus arteriosus (9/29), and complex transpositions of the great arteries (4/33). Additional vascular anomalies were present in 75%. Typical abnormal facial appearance at birth or at autopsy was observed in 80%, and thymus hypoplasia, in 76%. The pregnancy was terminated in 41 of 54 cases, including an intrauterine death in one case. The 22qdel was inherited in 7.7%. CONCLUSION Prevalence of the 22qdel is high in fetuses with CTMs. The risk of mental retardation associated with the respective risk of cardiac surgery for each type of CTM may strongly influence prenatal counseling.
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Affiliation(s)
- Y Boudjemline
- Service de Cardiologie Pédiatrique, Hôpital Necker-Enfants Malades, Paris, France
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56
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Li-Ling J. Connections between traditional Chinese medicine and congenital syndromes. ACTA ACUST UNITED AC 2001. [DOI: 10.1002/ajmg.1562] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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57
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Abstract
The development of fluorescence in situ hybridization (FISH)- and polymerase chain reaction (PCR)-based assays for the detection of deletions of chromosome 22q11.2 has enabled the medical community to offer couples at risk prenatal diagnostic testing. Current indications for testing include a previous child with a 22q11.2 deletion or DiGeorge/velocardiofacial syndrome, an affected parent with a 22q11.2 deletion, and in utero detection of a conotruncal cardiac defect. Antenatal knowledge of the deletion status provides couples and clinicians with an accurate diagnosis, prognostic information, and recurrence risk, which may assist couples with their reproductive decisions. However, there are limitations to prenatal testing, which should be reviewed prior to testing.
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Affiliation(s)
- D A Driscoll
- Department of Obstetrics and Gynecology, University of Pennsylvania, Philadelphia 19104, USA
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58
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Marino B, Digilio MC, Toscano A, Anaclerio S, Giannotti A, Feltri C, de Ioris MA, Angioni A, Dallapiccola B. Anatomic patterns of conotruncal defects associated with deletion 22q11. Genet Med 2001; 3:45-8. [PMID: 11339377 DOI: 10.1097/00125817-200101000-00010] [Citation(s) in RCA: 119] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
PURPOSE Patients with cardiovascular malformations (CVMs) and deletion 22q11 from our series were studied in order to (1) analyze the association with dysmorphic features and noncardiac anomalies, (2) identify specific cardiac patterns and the distinctive association with additional CVMs. METHODS From 1993 to 2000, 931 patients with CVM (95 with a clinical diagnosis of DiGeorge/velocardiofacial syndrome (DG/VCFS), 208 with different genetic syndromes, 628 without dysmorphic features) underwent accurate cardiac assessment, clinical and phenotypical examination, and screening for deletion 22q11 by fluorescence in situ hybridization (FISH). RESULTS Deletion 22q11 was detected in 88 of the total patients, and in 87 of the 95 patients with a clinical diagnosis of DG/VCFS. Only one patient among the 628 without dysmorphic features had deletion 22q11. Conotruncal heart defects were the most common CVMs, often presenting in association with additional anomalies in four areas of the cardiovascular system: (1) the aortic arch can be right sided, cervical, double, and the subclavian artery can be aberrant, (2) the pulmonary arteries can present discontinuity, diffuse hypoplasia, discrete stenosis, defect of arborization and major aortopulmonary collateral arteries (MAPCA), (3) the infundibular septum can be malaligned, hypoplastic, or absent, (4) the semilunar valves can be bicuspid, severely dysplastic, insufficient, or stenotic. CONCLUSION In subjects with deletion 22q11 CVM is virtually always associated with one or more noncardiac anomalies. Deletion 22q11 is exceptionally rare in children with nonsyndromic CVMs. Specific patterns of CVMs are observed in patients with deletion 22q11, including (1) anomalies of the aortic arch, (2) anomalies of the pulmonary arteries and of the pulmonary blood supply, (3) defects of the infundibular septum, (4) malformations of the semilunar valves. These additional CVMs may influence the surgical treatment of these patients.
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MESH Headings
- Abnormalities, Multiple/genetics
- Adolescent
- Aorta, Thoracic/abnormalities
- Child
- Child, Preschool
- Chromosome Deletion
- Chromosomes, Human, Pair 22
- DiGeorge Syndrome/diagnosis
- DiGeorge Syndrome/genetics
- Female
- Genotype
- Heart Defects, Congenital/diagnosis
- Heart Defects, Congenital/genetics
- Heart Septal Defects, Ventricular/diagnosis
- Heart Septal Defects, Ventricular/genetics
- Humans
- In Situ Hybridization, Fluorescence
- Infant
- Infant, Newborn
- Male
- Phenotype
- Pulmonary Atresia/diagnosis
- Pulmonary Atresia/genetics
- Tetralogy of Fallot/diagnosis
- Tetralogy of Fallot/genetics
- Truncus Arteriosus/abnormalities
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Affiliation(s)
- B Marino
- Department of Pediatric Cardiology, Bambino Gesù Hospital, Rome, Italy
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59
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Maeda J, Yamagishi H, Matsuoka R, Ishihara J, Tokumura M, Fukushima H, Ueda H, Takahashi E, Yoshiba S, Kojima Y. Frequent association of 22q11.2 deletion with tetralogy of Fallot. AMERICAN JOURNAL OF MEDICAL GENETICS 2000; 92:269-72. [PMID: 10842294 DOI: 10.1002/(sici)1096-8628(20000605)92:4<269::aid-ajmg9>3.0.co;2-l] [Citation(s) in RCA: 71] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Chromosome 22q11.2 deletion causes DiGeorge syndrome, velocardiofacial syndrome, conotruncal anomaly face syndrome with tetralogy of Fallot (TOF), and sporadic or familial TOF. To determine the prevalence and clinical importance of the 22q11.2 deletion in TOF, a series of 212 Japanese TOF patients was studied. The type of pulmonary blood supply, which may lead to various clinical outcomes, and other additional anomalies were evaluated clinically. The 22q11.2 deletion was diagnosed by fluorescence in situ hybridization with N25 and TUPLE1 probes. Of the 212 patients examined, 28 (13%) had a 22q11.2 deletion, the frequency being higher than that in TOF patients with trisomy 21. The prevalence of the deletion in TOF patients with pulmonary atresia (PA) plus major aortico-pulmonary collateral arteries (MAPCA) was significantly higher than the value in patients with PA plus patent ductus arteriosus (PDA) (P = 0.04) or with pulmonary stenosis (PS) (P < 0.0001). All 28 patients with 22q11.2 deletion had one or more extracardiac abnormalities. Four of 9 patients with the 22q11.2 deletion and TOF-PA-MAPCA suffered from bronchomalacia, while none of 19 patients with TOF-PA-PDA or TOF-PS manifested bronchomalacia (P = 0.006). These results indicate that 22q11.2 deletion is the most frequent cause of syndromic TOF, especially for TOF-PA-MAPCA, and bronchomalacia is the clinically most important associated anomaly in TOF-PA-MAPCA patients.
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Affiliation(s)
- J Maeda
- Department of Pediatrics, Keio University School of Medicine, Tokyo, Japan.
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60
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Digilio MC, Marino B, Musolino AM, Giannotti A, Dallapiccola B. Familial recurrence of nonsyndromic interrupted aortic arch and truncus arteriosus with atrioventricular canal. TERATOLOGY 2000; 61:329-31. [PMID: 10777827 DOI: 10.1002/(sici)1096-9926(200005)61:5<329::aid-tera3>3.0.co;2-c] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Multifactorial inheritance is probably involved in most cases of nonsyndromic conotruncal heart defects (CHDs), but Mendelian transmission is often suspected. RESULTS We report on a family with recurrence of nonsyndromic CTHD in two double first cousins; i.e., two brothers married two sisters. One of the cousins (case 1) had interrupted aortic arch (IAA) type B, while the other one (case 2) had truncus arteriosus (TA) with atrioventricular canal defect (AVCD). CONCLUSIONS Our family further supports monogenic inheritance of CTHDs. In addition, the presence of TA associated with AVCD in one of the patients confirms the higher occurrence of CTHD in families with complex TA. The absence of 22q11 microdeletion (del22q11) in our patients, as in several literature reports of familial CTHDs, supports the existence of genes different to those located on chromosome 22q11 which could be implicated in the pathogenesis of CTHDs.
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Affiliation(s)
- M C Digilio
- Department of Medical Genetics, Bambino Gesù Hospital, 00165 Rome, Italy
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61
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Abstract
BACKGROUND Interruption of the aortic arch (IAA) is a rare but severe anomaly associated with major intracardiac defects and with multisystem noncardiac malformations, recently linked to chromosome deletion of 22q11.2. METHODS The Baltimore-Washington Infant Study (1981-1989), a population-based epidemiologic study of cardiovascular malformations, evaluated 53 infants with IAA in comparison with 3,572 controls. Risk factors for the anatomic subtypes were evaluated in 14 cases of IAA type A and 32 cases of IAA type B, but no molecular genetic tests were available. The distribution of associated cardiac defects was similar for both types. RESULTS DiGeorge syndrome (DGS) occurred more frequently in IAA type B. Case-control comparisons demonstrated that infants in both groups were growth retarded at birth. A family history of noncardiac defects occurred only in IAA type B cases and included relatives with cleft lip and/or cleft palate. Candidate risk factors were associated only in type B cases and differed for those with (n = 10) and for those without (n = 19) DGS: a family history of noncardiac defects (odds ratio [OR] = 7.2, 95% confidence interval [CI] = 1.5-39.2) and maternal use of aspirin during the critical period (OR = 4.8, 95% CI = 1.3-25.4) occurred with DGS, while previous stillbirth (OR = 9.4, 95% CI = 1.3-53.1), bleeding during pregnancy (OR = 3.7, 95% CI = 1.4-11.4), and maternal exposure to arts/crafts paints (OR = 4.8, 95% CI = 1.3-17.4) were associated in those without DGS. CONCLUSIONS These findings confirm the heterogeneity of IAA and of the type B subtype. Risk factors specific for cases with DGS may open a window to further investigations of the etiology of IAA and of the associated molecular genetic abnormalities.
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Affiliation(s)
- C A Loffredo
- Department of Epidemiology and Preventive Medicine, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA.
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62
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Momma K, Ando M, Matsuoka R, Joo K. Interruption of the aortic arch associated with deletion of chromosome 22q11 is associated with a subarterial and doubly committed ventricular septal defect in Japanese patients. Cardiol Young 1999; 9:463-7. [PMID: 10535824 DOI: 10.1017/s1047951100005357] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECTIVES The purpose of this study was to clarify the clinical characteristics of interruption of the aortic arch associated with chromosome 22q11deletion. BACKGROUND About half of patients with interruption of the aortic arch between the left common carotid and the left subclavian artery have deletion of chromosome 22q11. METHODS In total, 20 patients with interruption of the aortic arch were studied with fluorescence in situ hybridization using peripheral lymphocytes and a DiGeorge syndrome chromosomal probe (Oncor N25). Cardiovascular anomalies in these patients were diagnosed by cross-sectional echocardiography and angiocardiography, and were confirmed at intracardiac repair. RESULTS Of 13 patients with interruption between the left common carotid artery and the left subclavian artery, seven had the deletion. All 7 also showed thymic hypoplasia and hypocalcemia, together with a nasal voice and peculiar facies. Six of the seven patients had complete deficiency of the muscular outlet septum, with the defect extending to the perimembranous area. Such complete absence of the muscular outlet septum was not present in any of the patients without the deletion. CONCLUSIONS Interruption of the aortic arch between the left common carotid and the left subclavian artery, absence of the thymus, and complete absence of the muscular outlet septum, were characteristic in Japanese patients with interruption of the aortic arch associated with deletion of chromosome 22q11.
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Affiliation(s)
- K Momma
- Department of Pediatric Cardiology, Heart Institute of Japan, Tokyo Women's Medical University
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63
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McElhinney DB, Anderson RH. Developmental anomalies of the outflow tracts and aortic arch: towards an understanding of the role of deletions within the 22nd chromosome. Cardiol Young 1999; 9:451-7. [PMID: 10535821 DOI: 10.1017/s1047951100005321] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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64
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Takahashi K, Kuwahara T, Nagatsu M. Interruption of the aortic arch at the isthmus with DiGeorge syndrome and 22q11.2 deletion. Cardiol Young 1999; 9:516-8. [PMID: 10535835 DOI: 10.1017/s1047951100005461] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
A 6-day-old male with interruption of the aortic arch at the isthmus (type A) had the typical phenotype of DiGeorge syndrome. There was also a doubly committed juxta-arterial ventricular septal defect and an unobstructed left ventricular outflow tract. Hypoplasia of the thymus was confirmed during a modified Blalock-Park operation. He had persistent hypocalcemia, and was susceptible to infection. He was subsequently revealed by the use of fluorescence in situ hybridization analysis to have 22q11.2 deletion. Interruption of the aortic arch at the isthmus is presumed to reflect abnormal fetal hemodynamics, and is considered a distinct pathogenetic entity from interruption between the left common carotid and subclavian arteries, the latter being the variant more frequently associated with DiGeorge syndrome. In our case, the 22q11.2 deletion likely played a major role in the etiology of the interrupted aortic arch.
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Affiliation(s)
- K Takahashi
- Division of Pediatric Cardiology, Gifu Prefecture Hospital, Japan.
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65
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Marino B, Digilio MC, Persiani M, Di Donato R, Toscano A, Giannotti A, Dallapiccola B. Deletion 22q11 in patients with interrupted aortic arch. Am J Cardiol 1999; 84:360-1, A9. [PMID: 10496456 DOI: 10.1016/s0002-9149(99)00297-0] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
Abstract
In our series of 27 children with various types of interruption of the aortic arch (IAA), deletion 22q11 is prevalent in patients with simple IAA type B, and is absent in patients with IAA type A and in those with associated additional major cardiac defects. Anomalies of the infundibular septum should be considered a characteristic aspect of children with IAA and deletion 22q11.
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Affiliation(s)
- B Marino
- Department of Pediatric Cardiology, Bambino Gesù Hospital, Rome, Italy
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66
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Yamagishi H, Garg V, Matsuoka R, Thomas T, Srivastava D. A molecular pathway revealing a genetic basis for human cardiac and craniofacial defects. Science 1999; 283:1158-61. [PMID: 10024240 DOI: 10.1126/science.283.5405.1158] [Citation(s) in RCA: 233] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Microdeletions of chromosome 22q11 are the most common genetic defects associated with cardiac and craniofacial anomalies in humans. A screen for mouse genes dependent on dHAND, a transcription factor implicated in neural crest development, identified Ufd1, which maps to human 22q11 and encodes a protein involved in degradation of ubiquitinated proteins. Mouse Ufd1 was specifically expressed in most tissues affected in patients with 22q11 deletion syndrome. The human UFD1L gene was deleted in all 182 patients studied with 22q11 deletion, and a smaller deletion of approximately 20 kilobases that removed exons 1 to 3 of UFD1L was found in one individual with features typical of 22q11 deletion syndrome. These data suggest that UFD1L haploinsufficiency contributes to the congenital heart and craniofacial defects seen in 22q11 deletion.
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Affiliation(s)
- H Yamagishi
- Department of Pediatrics, Division of Cardiology, University of Texas Southwestern Medical Center, 6000 Harry Hines Boulevard, Room NA8.124, Dallas, TX 75235-9148, USA
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67
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Lindsay EA, Baldini A. Congenital heart defects and 22q11 deletions: which genes count? MOLECULAR MEDICINE TODAY 1998; 4:350-7. [PMID: 9755454 DOI: 10.1016/s1357-4310(98)01302-1] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Hemizygous deletions on the long arm of chromosome 22 (del22q11) are a relatively common cause of congenital heart disease. For some specific heart defects such as interrupted aortic arch type B and tetralogy of Fallot with absent pulmonary valve, del22q11 is probably the most frequent genetic cause. Although extensive gene searches have been successful in discovering many novel genes in the deleted segment, standard positional cloning has so far failed to demonstrate a role for any of these genes in the disease. We show how the use of experimental animal models is beginning to provide an insight into the developmental role of some of these genes, while novel genome manipulation technologies promise to dissect the genetic aspects of this complex syndrome.
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Affiliation(s)
- E A Lindsay
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA
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68
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Rauch A, Hofbeck M, Leipold G, Klinge J, Trautmann U, Kirsch M, Singer H, Pfeiffer RA. Incidence and significance of 22q11.2 hemizygosity in patients with interrupted aortic arch. ACTA ACUST UNITED AC 1998. [DOI: 10.1002/(sici)1096-8628(19980724)78:4<322::aid-ajmg4>3.0.co;2-n] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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69
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Abstract
Congenital heart defects (CHD) constitute the single most common anatomic class of birth defects and are a major cause of infant mortality. Correlation of normal and pathological embryology/anatomy has led to the formulation of mechanistic models, but there is limited understanding of the genetic basis for the inferred embryological processes. Most evidence points to extensive etiologic heterogeneity and a re-evaluation of simple multifactorial models is required. The recent identification of several genes responsible for congenital heart defects in the context of more complex clinical disorders provides significant entry points for the genetic analysis of human heart development. The association of aneusomies (particularly microdeletion syndromes) with specific cardiac lesions provides further strong support for mechanistic classification. Studies in the mouse are laying the groundwork for a comprehensive genetic model of cardiac organogenesis. Nevertheless, the basis for the large majority of CHD, especially isolated defects, remains obscure. Dissection of the genetic components of CHD is one of the greatest challenges in medical genetics for the coming decades.
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Affiliation(s)
- J W Belmont
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030, USA.
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