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Analphoid supernumerary marker chromosome characterized by aCGH and FISH as inv dup(3)(q25.33qter) de novo in a child with dysmorphic features and streaky pigmentation: case report
Sabita K Murthy, Ashok K Malhotra, Preenu S Jacob, Sehba Naveed, Eman EM Al-Rowaished, Sara Mani, Shabeer Padariyakam, R Pramathan, Ravi Nath, Mahmoud Al-Ali, Lihadh Al-Gazali
Molecular Cytogenetics , 2008, DOI: 10.1186/1755-8166-1-19
Abstract: We describe here a one month old female child with several dysmorphic features and with a de novo analphoid supernumerary marker chromosome only in cultured skin fibroblast cells and not in lymphocytes. The marker was characterized as analphoid inversion-duplication 3q25.33-qter by oligo array comparative genomic hybridization (aCGH) and fluorescence in situ hybridization (FISH) studies. The final skin fibroblast karyotype was interpreted as 47,XX,+der(3).ish inv dup(3)(qter-q25.33::q25.33-qter)(subtel 3q+,subtel 3q+) de novo.In addition to the eight reported cases of analphoid inversion-duplication 3q supernumerary marker in the literature, this is yet another case of 3q sSMC with a new breakpoint at 3q25.33 and with varying phenotype as described in the case report. Identification of more and more similar cases of analphoid inversion-duplication 3q marker will help in establishing a better genotype-phenotype correlation. The study further demonstrates that aCGH in conjunction with routine cytogenetics and FISH is very useful in precisely identifying and characterizing a marker chromosome, and more importantly help in providing with an accurate genetic diagnosis and better counseling to the family.Small supernumerary marker chromosomes occur in 0.075% of unselected prenatal cases and in 0.044% of consecutively studied postnatal cases, and majority of them are de novo in origin [1-4]. Phenotype of individuals with de novo sSMC vary from normal to extremely mild or severe, depending on the chromosomal region involved and the euchromatic content present [5-7]. Although a number of reports describe the occurrence of a variety of sSMC for nearly all the chromosomes, the number for each type is not large enough to suggest a good genotype-phenotype correlation for a given sSMC, except for inv dup(15) and inv dup(22) where the phenotypic consequences are well described [6,8-10]. We describe here the phenotype and corresponding molecular cytogenetic results of a child with
The inv dup (15) or idic (15) syndrome (Tetrasomy 15q)
Agatino Battaglia
Orphanet Journal of Rare Diseases , 2008, DOI: 10.1186/1750-1172-3-30
Abstract: Chromosome region 15q11q13, known for its instability, is highly susceptible to clinically relevant genomic rearrangements, such as supernumerary marker chromosomes formed by the inverted duplication of proximal chromosome 15. Inv dup(15) results in tetrasomy 15p and partial tetrasomy 15q. The large rearrangements, containing the Prader-Willi/Angelman syndrome critical region (PWS/ASCR), are responsible for the inv dup(15) or idic(15) syndrome. Diagnosis is achieved by standard cytogenetics and FISH analysis, using probes both from proximal chromosome 15 and from the PWS/ASCR. Microsatellite analysis on parental DNA or methylation analysis on the proband DNA, are also needed to detect the parent-of-origin of the inv dup(15) chromosome. Array CGH has been shown to provide a powerful approach for identifying and detecting the extent of the duplication. The possible occurrence of double supernumerary isodicentric chromosomes derived from chromosome 15, resulting in partial hexasomy of the maternally inherited PWS/ASCR, should be considered in the differential diagnosis. Large idic(15) are nearly always sporadic. Antenatal diagnosis is possible. Management of inv dup(15) includes a comprehensive neurophysiologic and developmental evaluation. Survival is not significantly reduced.The inv dup(15) or idic(15) syndrome can also be termed "tetrasomy 15q". About 160 patients have been reported in the medical literature [1-5].The inv dup(15) or idic(15) syndrome (inverted duplication of proximal chromosome 15 or isodicentric 15 chromosome) displays distinctive clinical findings represented by early central hypotonia, developmental delay and intellectual disability, epilepsy, and autistic behavior. The latter is characterized by lack of social interaction, non-functional use of objects, primordial type of exploration, stereotypies, absent or very poor echolalic language, limited comprehension, and poor intention to communicate. Physically, there are only minor anomalies. Altoge
De Novo Unbalanced Translocations in Prader-Willi and Angelman Syndrome Might Be the Reciprocal Product of inv dup(15)s  [PDF]
Elena Rossi, Roberto Giorda, Maria Clara Bonaglia, Stefania Di Candia, Elena Grechi, Adriana Franzese, Fiorenza Soli, Francesca Rivieri, Maria Grazia Patricelli, Donatella Saccilotto, Aldo Bonfante, Sabrina Giglio, Silvana Beri, Mariano Rocchi, Orsetta Zuffardi
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0039180
Abstract: The 15q11-q13 region is characterized by high instability, caused by the presence of several paralogous segmental duplications. Although most mechanisms dealing with cryptic deletions and amplifications have been at least partly characterized, little is known about the rare translocations involving this region. We characterized at the molecular level five unbalanced translocations, including a jumping one, having most of 15q transposed to the end of another chromosome, whereas the der(15)(pter->q11-q13) was missing. Imbalances were associated either with Prader-Willi or Angelman syndrome. Array-CGH demonstrated the absence of any copy number changes in the recipient chromosome in three cases, while one carried a cryptic terminal deletion and another a large terminal deletion, already diagnosed by classical cytogenetics. We cloned the breakpoint junctions in two cases, whereas cloning was impaired by complex regional genomic architecture and mosaicism in the others. Our results strongly indicate that some of our translocations originated through a prezygotic/postzygotic two-hit mechanism starting with the formation of an acentric 15qter->q1::q1->qter representing the reciprocal product of the inv dup(15) supernumerary marker chromosome. An embryo with such an acentric chromosome plus a normal chromosome 15 inherited from the other parent could survive only if partial trisomy 15 rescue would occur through elimination of part of the acentric chromosome, stabilization of the remaining portion with telomere capture, and formation of a derivative chromosome. All these events likely do not happen concurrently in a single cell but are rather the result of successive stabilization attempts occurring in different cells of which only the fittest will finally survive. Accordingly, jumping translocations might represent successful rescue attempts in different cells rather than transfer of the same 15q portion to different chromosomes. We also hypothesize that neocentromerization of the original acentric chromosome during early embryogenesis may be required to avoid its loss before cell survival is finally assured.
Trisomy Chromosome (22)(q13.1-qter) as a Result of Paternal Inversion (22)(p11q13.1) Proved Using Region-Specific FISH Probes  [PDF]
Jia-Woei Hou
Chang Gung Medical Journal , 2005,
Abstract: We present a male infant with multiple congenital anomalies including severe growthretardation, microcephaly, hypertelorism, low-set ears, bilateral cleft lip and palate, micrognathia,cryptorchidism with hypospadias, hemivertebrae, and complex heart defects. Thekaryotype was 46, XY, rec(22) dup(22q) inv(22)(p11q13)pat. The duplicated segment (q13.1qter), a result of an unbalanced recombinant derived from the paternal inversion(22)(p11q13.1), was confirmed using results of silver staining for nucleolar organizerregions (NOR) and fluorescence in situ hybridization with region-specific probes(D22S75/D22S39 and Mbcr). This case further delineated the clinical entity of duplicated22q13 or distal trisomy 22.
Detailed analysis of 15q11-q14 sequence corrects errors and gaps in the public access sequence to fully reveal large segmental duplications at breakpoints for Prader-Willi, Angelman, and inv dup(15) syndromes
Andrew J Makoff, Rachel H Flomen
Genome Biology , 2007, DOI: 10.1186/gb-2007-8-6-r114
Abstract: Our analysis has revealed assembly errors, including contig NT_078094 being in the wrong orientation, and has enabled most of the gaps between contigs to be closed. We have constructed a map in which segmental duplications are no longer interrupted by gaps and which together reveals a complex region. There are two pairs of large direct repeats that are located in regions consistent with the two classes of deletions associated with Prader-Willi and Angelman syndromes. There are also large inverted repeats that account for the formation of the observed supernumerary marker chromosomes containing two copies of the proximal end of 15q and associated with autism spectrum disorders when involving duplications of maternal origin (inv dup[15] syndrome).We have produced a segmental map of 15q11-q14 that reveals several large direct and inverted repeats that are incompletely and inaccurately represented on the current human genome sequence. Some of these repeats are clearly responsible for deletions and duplications in known genomic disorders, whereas some may increase susceptibility to other disorders.The proximal end of chromosome 15 contains many segmental duplications and is especially susceptible to genomic rearrangements and genomic disorders (recurrent disorders that are a consequence of the genomic architecture). Among the most well studied of these are Prader-Willi syndrome (PWS) and Angelman syndrome (AS) syndromes, of which about 75% are caused by interstitial deletions in 15q11-13. Because a cluster of imprinted genes lie in the deleted region, the phenotype is dependent on the parental origin of the affected chromosome. Deletions on the paternal chromosome result in PWS, whereas deletions on the maternal chromosome cause AS [1]. These deletions occur with an approximate frequency of 1 per 10,000 live births, and they generally fall into two size classes with breakpoints (BPs) within three discrete regions (BP1 to BP3) [2]. Both classes share the same distal break
Abnormal Intracellular Accumulation and Extracellular Aβ Deposition in Idiopathic and Dup15q11.2-q13 Autism Spectrum Disorders  [PDF]
Jerzy Wegiel, Janusz Frackowiak, Bozena Mazur-Kolecka, N. Carolyn Schanen, Edwin H. Cook, Marian Sigman, W. Ted Brown, Izabela Kuchna, Jarek Wegiel, Krzysztof Nowicki, Humi Imaki, Shuang Yong Ma, Abha Chauhan, Ved Chauhan, David L. Miller, Pankaj D. Mehta, Michael Flory, Ira L. Cohen, Eric London, Barry Reisberg, Mony J. de Leon, Thomas Wisniewski
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0035414
Abstract: Background It has been shown that amyloid ? (Aβ), a product of proteolytic cleavage of the amyloid β precursor protein (APP), accumulates in neuronal cytoplasm in non-affected individuals in a cell type–specific amount. Methodology/Principal Findings In the present study, we found that the percentage of amyloid-positive neurons increases in subjects diagnosed with idiopathic autism and subjects diagnosed with duplication 15q11.2-q13 (dup15) and autism spectrum disorder (ASD). In spite of interindividual differences within each examined group, levels of intraneuronal Aβ load were significantly greater in the dup(15) autism group than in either the control or the idiopathic autism group in 11 of 12 examined regions (p<0.0001 for all comparisons; Kruskall-Wallis test). In eight regions, intraneuronal Aβ load differed significantly between idiopathic autism and control groups (p<0.0001). The intraneuronal Aβ was mainly N-terminally truncated. Increased intraneuronal accumulation of Aβ17–40/42 in children and adults suggests a life-long enhancement of APP processing with α-secretase in autistic subjects. Aβ accumulation in neuronal endosomes, autophagic vacuoles, Lamp1-positive lysosomes and lipofuscin, as revealed by confocal microscopy, indicates that products of enhanced α-secretase processing accumulate in organelles involved in proteolysis and storage of metabolic remnants. Diffuse plaques containing Aβ1–40/42 detected in three subjects with ASD, 39 to 52 years of age, suggest that there is an age-associated risk of alterations of APP processing with an intraneuronal accumulation of a short form of Aβ and an extracellular deposition of full-length Aβ in nonfibrillar plaques. Conclusions/Significance The higher prevalence of excessive Aβ accumulation in neurons in individuals with early onset of intractable seizures, and with a high risk of sudden unexpected death in epilepsy in autistic subjects with dup(15) compared to subjects with idiopathic ASD, supports the concept of mechanistic and functional links between autism, epilepsy and alterations of APP processing leading to neuronal and astrocytic Aβ accumulation and diffuse plaque formation.
How Accurate is inv(A)*b?  [PDF]
Alex Druinsky,Sivan Toledo
Computer Science , 2012,
Abstract: Several widely-used textbooks lead the reader to believe that solving a linear system of equations Ax = b by multiplying the vector b by a computed inverse inv(A) is inaccurate. Virtually all other textbooks on numerical analysis and numerical linear algebra advise against using computed inverses without stating whether this is accurate or not. In fact, under reasonable assumptions on how the inverse is computed, x = inv(A)*b is as accurate as the solution computed by the best backward-stable solvers. This fact is not new, but obviously obscure. We review the literature on the accuracy of this computation and present a self-contained numerical analysis of it.
Novel Neurovascular Protective Agents: Effects of INV-155, INV-157, INV-159, and INV-161 versus Lipoic Acid and Captopril in a Rat Stroke Model  [PDF]
Barry J. Connell,Bobby V. Khan,Desikan Rajagopal,Tarek M. Saleh
Cardiology Research and Practice , 2012, DOI: 10.1155/2012/319230
Abstract: Background. Lipoic acid (LA), which has significant antioxidant properties, may also function as a potent neuroprotectant. The synthetic compounds INV-155, INV-157, INV-159, and INV-161 are physiochemical combinations of lipoic acid and captopril. We sought to determine if these compounds have neuroprotective potential following middle cerebral artery occlusion (MCAO) in rats. Methods. Male Sprague-Dawley rats were injected intravenously with captopril (1–50?mg/kg) 30 minutes prior to MCAO. Blood pressure, heart rate, baroreceptor reflex sensitivity, and infarct size were measured. In addition, dose response effect on infarct size and cardiovascular parameters was determined using INV-155, INV-157, INV-159, and INV-161 and compared to captopril and LA. Results. Pretreatment with captopril and LA at all doses tested was neuroprotective. The compounds INV-159 (0.5–10?mg/kg) and INV-161 (1–10?mg/kg) produced a significant,dose-dependent decrease in infarct size. In contrast, INV-155 and INV-157 had no effect on infarct size. Conclusions. Combined pretreatment with captopril potentiated the neuroprotective benefit observed following LA alone. Both INV-159 and INV-161 were also neuroprotective. These results suggest that patients taking combinations of captopril and LA, either as combination therapy or in the form of INV-159 or INV-161, may also benefit from significant protection against cerebral infarction. 1. Introduction Hypertension prevalence is highly variable among populations worldwide. In the United States there is a disproportionate burden of this disease and its complications in African Americans [1]. African Americans have the highest prevalence of hypertension in the world, significantly higher than people of African origin living outside the United States [2]. According to the 2003-2004 National Health and Nutrition Examination Survey (NHANES) hypertension prevalence is 39.1% in African Americans and 28.5% in White Americans [3]. The increased prevalence of hypertension in African-Americans has been attributed to both genetic and environmental factors [4]. Additionally, hypertension is usually observed at a younger age in African-Americans and it results in more severe disease complications. This results in a significantly higher hypertension related mortality rate for African Americans, 49.9% and 40.6% for African American men and women, respectively, compared to 17.9% for the overall US population in 2004 [1]. Cardiometabolic syndrome, a constellation of common cardiovascular risk factors (obesity/overweight, atherogenic dyslipidemia,
Multiple Renal Cyst Development but Not Situs Abnormalities in Transgenic RNAi Mice against Inv::GFP Rescue Gene  [PDF]
Yuki Kamijho, Yayoi Shiozaki, Eiki Sakurai, Kazunori Hanaoka, Daisuke Watanabe
PLOS ONE , 2014, DOI: 10.1371/journal.pone.0089652
Abstract: In this study we generated RNA interference (RNAi)-mediated gene knockdown transgenic mice (transgenic RNAi mice) against the functional Inv gene. Inv mutant mice show consistently reversed internal organs (situs inversus), multiple renal cysts and neonatal lethality. The Inv::GFP-rescue mice, which introduced the Inv::GFP fusion gene, can rescue inv mutant mice phenotypes. This indicates that the Inv::GFP gene is functional in vivo. To analyze the physiological functions of the Inv gene, and to demonstrate the availability of transgenic RNAi mice, we introduced a short hairpin RNA expression vector against GFP mRNA into Inv::GFP-rescue mice and analyzed the gene silencing effects and Inv functions by examining phenotypes. Transgenic RNAi mice with the Inv::GFP-rescue gene (Inv-KD mice) down-regulated Inv::GFP fusion protein and showed hypomorphic phenotypes of inv mutant mice, such as renal cyst development, but not situs abnormalities or postnatal lethality. This indicates that shRNAi-mediated gene silencing systems that target the tag sequence of the fusion gene work properly in vivo, and suggests that a relatively high level of Inv protein is required for kidney development in contrast to left/right axis determination. Inv::GFP protein was significantly down-regulated in the germ cells of Inv-KD mice testis compared with somatic cells, suggesting the existence of a testicular germ cell-specific enhanced RNAi system that regulates germ cell development. The Inv-KD mouse is useful for studying Inv gene functions in adult tissue that are unable to be analyzed in inv mutant mice showing postnatal lethality. In addition, the shRNA-based gene silencing system against the tag sequence of the fusion gene can be utilized as a new technique to regulate gene expression in either in vitro or in vivo experiments.
A fic o de Cony: invólucros da memória  [cached]
Milton Hermes Rodrigues
Acta Scientiarum : Language and Culture , 2010,
Abstract: BUENO, Raquel Illescas. Os invólucros da memória na fic o de Carlos Heitor Cony. Rio de Janeiro: Academia Brasileira de Letras, 2008. 325 p. ISBN 978-85-7440-118-8.
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