scholarly journals Benign and Unknown Copy Number Variations in Bulgarian Patients with Intellectual Disability and Congenital Malformations

2013 ◽  
Vol 27 (6) ◽  
pp. 4304-4307
Author(s):  
Savina Petrova Hadjidekova ◽  
Daniela Mircheva Avdjieva-Tzavella ◽  
Blaga Borisova Rukova ◽  
Desislava Valentinova Nesheva ◽  
Radka Stefanova Tincheva ◽  
...  
Keyword(s):  
Intellectual Disability ◽  
Copy Number ◽  
Congenital Malformations ◽  
Copy Number Variations

X-linked CNV and skewed X-chromosome inactivation

2020 ◽  
pp. 19-21
Author(s):  
Е.А. Фонова ◽  
Е.Н. Толмачева ◽  
А.А. Кашеварова ◽  
М.Е. Лопаткина ◽  
К.А. Павлова ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Intellectual Disability ◽  
X Chromosome ◽  
Copy Number ◽  
Copy Number Variations ◽  
X Chromosome Inactivation ◽  
Chromosome Inactivation ◽  
Chromosome X ◽  
Skewed X Chromosome Inactivation

Смещение инактивации Х-хромосомы может быть следствием и маркером нарушения клеточной пролиферации при вариациях числа копий ДНК на Х-хромосоме. Х-сцепленные CNV выявляются как у женщин с невынашиванием беременности и смещением инактивации Х-хромосомы (с частотой 33,3%), так и у пациентов с умственной отсталостью и смещением инактивацией у их матерей (с частотой 40%). A skewed X-chromosome inactivation can be a consequence and a marker of impaired cell proliferation in the presence of copy number variations (CNV) on the X chromosome. X-linked CNVs are detected in women with miscarriages and a skewed X-chromosome inactivation (with a frequency of 33.3%), as well as in patients with intellectual disability and skewed X-chromosome inactivation in their mothers (with a frequency of 40%).

scholarly journals Lessons Learned from CNV Analysis of Major Birth Defects

2020 ◽  
Vol 21 (21) ◽  
pp. 8247
Author(s):  
Alina Christine Hilger ◽  
Gabriel Clemens Dworschak ◽  
Heiko Martin Reutter
Keyword(s):  
Birth Defects ◽  
Copy Number ◽  
Congenital Malformations ◽  
De Novo ◽  
Copy Number Variations ◽  
Lessons Learned ◽  
Organ System ◽  
Molecular Karyotyping ◽  
The Past ◽  
Single Organ

The treatment of major birth defects are key concerns for child health. Hitherto, for the majority of birth defects, the underlying cause remains unknown, likely to be heterogeneous. The implicated mortality and/or reduced fecundity in major birth defects suggest a significant fraction of mutational de novo events among the affected individuals. With the advent of systematic array-based molecular karyotyping, larger cohorts of affected individuals have been screened over the past decade. This review discusses the identification of disease-causing copy-number variations (CNVs) among individuals with different congenital malformations. It highlights the differences in findings depending on the respective congenital malformation. It looks at the differences in findings of CNV analysis in non-isolated complex congenital malformations, associated with central nervous system malformations or intellectual disabilities, compared to isolated single organ-system malformations. We propose that the more complex an organ system is, and the more genes involved during embryonic development, the more likely it is that mutational de novo events, comprising CNVs, will confer to the expression of birth defects of this organ system.

scholarly journals A Case With 4 de Novo Copy Number Variations With Clinical Features That Overlap 1q43q44 Microdeletion and 3q29 Microduplication Syndromes

2018 ◽  
Vol 5 ◽  
pp. 2329048X1879820
Author(s):  
Miriam Kessi ◽  
Jing Peng ◽  
Lifen Yang ◽  
Haolin Duan ◽  
Yulin Tang ◽  
...  
Keyword(s):  
Intellectual Disability ◽  
Corpus Callosum ◽  
Copy Number ◽  
De Novo ◽  
Copy Number Variations ◽  
Language Delay ◽  
Global Developmental Delay ◽  
Recurrent Infections ◽  
Dental Anomalies ◽  
Microdeletion Syndrome

1q43q44 microdeletion syndrome is characterized by intellectual disability/global developmental delay, epilepsy, dysmorphic facies, stereotypic movement, language delay, recurrent infections, dental anomalies, and hand and foot anomalies. Microcephaly and corpus callosum dysplasia are present in some cases depending on gene content. 3q29 microduplication syndrome is characterized by intellectual disability, language delay, microcephaly, and dental anomalies. We report the first case with 4 de novo copy number variations with clinical features which overlap 1q43q44 microdeletion and 3q29 microduplication syndromes. Our case presented with global developmental delay, epilepsy, recurrent infections, stereotypic movements, speech delay, microcephaly, facial dysmorphism, bilateral clinodactyly, and small puffy feet with metatarsus varus; however, she had no corpus callosum dysplasia. Our case highlights the role of multiple copy number variations in the occurrence of a certain phenotype. Moreover, it supports the theory that the loss of HNRNPU gene function cannot explain the occurrence of microcephaly and abnormalities of the corpus callosum in 1q43q44 microdeletion syndrome.

scholarly journals Phenotypic and Molecular Cytogenetic Analysis of a Case of Monosomy 1p36 Syndrome due to Unbalanced Translocation

2020 ◽  
Vol 11 (5-6) ◽  
pp. 284-295
Author(s):  
Dalia F. Hussen ◽  
Alaa K. Kamel ◽  
Mona K. Mekkawy ◽  
Engy A. Ashaat ◽  
Mona O. El Ruby
Keyword(s):  
Intellectual Disability ◽  
Microarray Analysis ◽  
Cytogenetic Analysis ◽  
Copy Number ◽  
Clinical Manifestations ◽  
Copy Number Variations ◽  
Chromosomal Microarray Analysis ◽  
Fish Analysis ◽  
Unbalanced Translocation ◽  
Genotype Correlation

Monosomy 1p36 syndrome is one of the most common submicroscopic deletion syndromes, which is characterized by the presence of delayed developmental milestones, intellectual disability, and clinically recognizable dysmorphic craniofacial features. The syndrome comprises 4 cytogenetic groups including pure terminal deletions, interstitial deletions, complex rearrangements, and derivative chromosomes 1 due to unbalanced translocations, where unbalanced translocations represent the least percentage of all cases of monosomy 1p36 (7%). Most patients with monosomy 1p36 due to an unbalanced translocation can be cytogenetically diagnosed using conventional techniques. However, chromosomal microarray analysis is mandatory in these cases to detect copy number variance and size of the deletion and allows for setting a phenotype-genotype correlation. Here, we studied a 1.5-year-old female patient who showed intellectual disability, delayed milestones, hypotonia, seizures, and characteristic dysmorphic features including brachycephaly, straight eyebrows, deep-set eyes, downslanting palpebral fissures, midface hypoplasia, depressed nasal bridge, long philtrum, and pointed chin. Conventional cytogenetic analysis (CCA), microarray study, and fluorescence in situ hybridization (FISH) analysis were performed. CCA showed a translocation involving chromosomes 1 and 21, 45,XX,der(1)t(1;21)(p36.32;q21.1)dn. Microarray analysis revealed copy number losses at both 1p36 and proximal 21q. FISH confirmed the presence of the 1p36 deletion, but was not performed for 21q. We have concluded that phenotype-genotype correlation for monosomy 1p36 syndrome can be performed for the fundamental clinical manifestations; however, the final aspect of the syndrome depends on composite factors. Monosomy 1p36 due to unbalanced translocation may present either classically or with additional altered features of various severity based on the copy number variations involving different chromosomes.

scholarly journals miRNA and miRNA target genes in copy number variations occurring in individuals with intellectual disability

BMC Genomics ◽  
2013 ◽  
Vol 14 (1) ◽  
pp. 544 ◽  
Author(s):  
Ying Qiao ◽  
Chansonette Badduke ◽  
Eloi Mercier ◽  
Suzanne ME Lewis ◽  
Paul Pavlidis ◽  
...  
Keyword(s):  
Intellectual Disability ◽  
Copy Number ◽  
Mirna Target ◽  
Target Genes ◽  
Copy Number Variations

scholarly journals Xp11.2 Duplication in Females: Unique Features of a Rare Copy Number Variation

2021 ◽  
Vol 12 ◽  
Author(s):  
Márta Czakó ◽  
Ágnes Till ◽  
Judith Zima ◽  
Anna Zsigmond ◽  
András Szabó ◽  
...  
Keyword(s):  
Intellectual Disability ◽  
Copy Number Variation ◽  
Copy Number ◽  
Neurodevelopmental Disorder ◽  
Copy Number Variations ◽  
Pathogenic Role ◽  
Routine Application ◽  
Phenotype Analysis ◽  
Number Variation ◽  
Minor Anomalies

Among the diseases with X-linked inheritance and intellectual disability, duplication of the Xp11.23p11.22 region is indeed a rare phenomenon, with less than 90 cases known in the literature. Most of them have been recognized with the routine application of array techniques, as these copy number variations (CNVs) are highly variable in size, occurring in recurrent and non-recurrent forms. Its pathogenic role is not debated anymore, but the information available about the pathomechanism, especially in affected females, is still very limited. It has been observed that the phenotype in females varies from normal to severe, which does not correlate with the size of the duplication or the genes involved, and which makes it very difficult to give an individual prognosis. Among the patients studied by the authors because of intellectual disability, epilepsy, and minor anomalies, overlapping duplications affecting the Xp11.23p11.22 region were detected in three females. Based on our detailed phenotype analysis, we concluded that Xp11.23p11.22 duplication is a neurodevelopmental disorder.

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