Microdeletion Syndrome (microdeletion + syndrome)

Distribution by Scientific Domains


Selected Abstracts


Homozygous microdeletion of chromosome 4q11-q12 causes severe limb-girdle muscular dystrophy type 2E with joint hyperlaxity and contractures,,

HUMAN MUTATION, Issue 3 2005
Angela M. Kaindl
Abstract Microdeletion syndromes are commonly transmitted as dominant traits and are frequently associated with variably expressed pleiotropic phenotypes. Nonlethal homozygous microdeletions, on the other hand, are very rare. Here, we delineate the fifth and so far largest homozygous microdeletion in nonmalignancies of approximately 400 kb on chromosome 4q11-q12 in a large consanguineous East-Anatolian family with six affected patients. The deleted region contains the beta-sarcoglycan gene (SGCB), the predicted gene SPATA18 (spermatogenesis associated 18 homolog) and several expressed sequence tags. Patients presented with a severe and progressive Duchenne-like muscular dystrophy phenotype, a combination of hyperlaxity and joint contractures, chest pain, palpitations, and dyspnea. © 2005 Wiley-Liss, Inc. [source]


Evidence by Expression Analysis of Candidate Genes for Congenital Heart Defects in the NF1 Microdeletion Interval

ANNALS OF HUMAN GENETICS, Issue 5 2005
M. Venturin
Summary It was recently reported that congenital heart disease is significantly more frequent in patients with NF1 microdeletion syndrome than in those with classical NF1. The outcome of congenital heart disease in this subset of patients is likely caused by the haploinsufficiency of gene/s in the deletion interval. Following in silico analysis of the deleted region, we found two genes known to be expressed in adult heart, the Joined to JAZF1 (SUZ12) and the Centaurin-alpha 2 (CENTA2) genes, and seven other genes with poorly defined patterns of expression and function. With the aim of defining their expression profiles in human fetal tissues (15th,21st weeks of gestation), expression analysis by RT-PCR and Northern blotting was performed. C17orf40, SUZ12 and CENTA2 were found to be mainly expressed in fetal heart, and following RT-PCR on mouse embryos and embryonic heart and brain at different stages of development, we found that the orthologous genes C17orf40, Suz12 and Centa2 are also expressed in early stages of development, before and during the formation of the four heart chambers. The presence of binding sites for Nkx2-5, a transcription factor expressed early in heart development, in all three mouse orthologous genes was predicted by bioinformatics, thus reinforcing the hypothesis that these genes might be involved in heart development and may be plausible candidates for congenital heart disease. [source]


Thyroid function and morphology in subjects with microdeletion of chromosome 22q11 (del(22)(q11))

CLINICAL ENDOCRINOLOGY, Issue 6 2010
Stefano Stagi
Summary Introduction, Monoallelic microdeletion of chromosome 22q11 (22q11DS) is considered to be the commonest human microdeletion syndrome. Abnormalities of thyroid function are sporadically reported in this syndrome, but very few studies have specifically assessed this issue, and thyroid morphology has not been systematically studied. Design, To evaluate the prevalence of abnormalities of thyroid function and morphology in a cohort of paediatric and adult patients with 22q11DS. Methods, Thirty patients with 22q11DS (median age 9·7, range 1·5,43·9 years) were studied. In all subjects, serum free-T3, free-T4, TSH, thyroperoxidase, thyroglobulin, and TSHr auto-antibodies, as well as thyroid ultrasonographic data, were evaluated and compared with age- and sex-matched healthy control groups, for paediatric and adult patients. Results, Fourteen (46·6%) patients showed thyroid hypoplasia involving the entire gland. In all the patients, the volume of the left lobe of the thyroid was significantly reduced (P < 0·01). Among the subjects with thyroid hypoplasia, 10 out of 14 (71%) showed a concomitant heart malformation, a condition that was present in five (31%) of the subjects with a normal thyroid volume (P < 0·05). Seven (23·3%) cases of subclinical hypothyroidism and one (3·3%) case of overt hypothyroidism were identified. Three (10%) patients were positive for thyroid auto-antibodies. Of the patients with overt and subclinical hypothyroidism, five out of eight (62·5%) patients showed thyroid hypoplasia. Conclusions, This study confirms the presence of alterations of thyroid function in 22q11DS, and also suggests a frequent occurrence of abnormalities in thyroid morphology in these subjects. Patients with 22q11DS should be monitored for thyroid function, and thyroid ultrasound screening should be considered, especially in those patients with changes in thyroid function or congenital heart malformations. The possible relationship between developmental abnormalities in the heart and the thyroid gland should be confirmed. [source]


Diagnostic yield by supplementing prenatal metaphase karyotyping with MLPA for microdeletion syndromes and subtelomere imbalances

PRENATAL DIAGNOSIS, Issue 10 2010
S. Kjaergaard
Abstract Objective The aim of the study was to retrospectively assess the relevance of using multiplex ligation-dependent probe amplification (MLPA) for detection of selected microdeletion syndromes (22q11, Prader,Willi/Angelman, Miller,Dieker, Smith,Magenis, 1p-, Williams), the reciprocal microduplication syndromes and imbalance at the subtelomere regions of chromosomes in a routine prenatal setting. Method A total of 530 prenatal samples were analysed by commercial MLPA kits (SALSA P064, P036 and P069) in addition to rapid aneuploidy testing and G-band karyotyping. Results Among the prenatal samples with a normal metaphase karyotype, nine submicroscopic imbalances were detected: seven 22q11 deletions (Velocardiofacial/DiGeorge syndrome), one 15q11deletion (Prader,Willi syndrome) and one terminal deletion of the short arm of chromosome 4 (Wolf,Hirschhorn syndrome). All imbalances were found in amniocentesis (AC) taken due to fetal structural malformation and/or other ultrasound scan (US) detected abnormality. The diagnostic yield was 4.1% in the subgroup with structural malformation and 1.6% in the subgroup with other US abnormality. Conclusion The data set substantiates that additional MLPA analyses for selected microdeletions and subtelomere imbalances are valuable in routine prenatal diagnostics, when a malformation(s) and/or other abnormalities are detected by US. In contrast, the additional MLPA analyses gave no diagnostic yield in case of increased nuchal translucency (NT). Copyright © 2010 John Wiley & Sons, Ltd. [source]