Proximal interstitial 1p36 deletion syndrome: the most proximal 3.5-Mb microdeletion identified on a dysmorphic and mentally retarded patient with inv(3)(p14.1q26.2)

From the investigation by microarray-based comparative genomic hybridization (aCGH), a new syndrome with “atypical” proximal interstitial deletion of 1p36.23-36.11 has been suggested. Here, we report on an 8.5-year-old girl with psychomotor developmental delay and a dysmorphic appearance. Although her G-banded chromosomal analysis showed inv(3)(p14.1q26.2), detailed FISH analyses denied pathogenic deletions around the breakpoints of chromosome 3. Accordingly, aCGH analysis was performed to identify a genomic aberration related to her phenotype, and a 3.5-Mb interstitial deletion of 1p36.13-36.12 was revealed. This deletion was the most proximal interstitial deletion of 1p36. Compared to the previously reported patients, abnormally shaped teeth, delayed tooth eruption, and leg malformation are unique phenotypes only to this patient, which might be due to the centromeric unique deletion region with 0.8-Mb.     

Prader-Willi syndrome: Diagnostic strategy with a cytogenetic and molecular approach

Prader-Willi syndrome (PWS) is a disorder characterized by neonatal hypotonia with poor suck, mild to moderate mental retardation, obesity beginning after 3 yr of age, hypogonadism and characteristic facial features. High resolution cytogenetic studies showed a deletion of the proximal chromosome 15q(q11–q13) region in approximately 50%. Interestingly, the same deletion was described in another distinct mental disorder: the Angelman syndrome (AS). This deletion was confirmed by molecular analyses, and a new mechanism was reported: uniparental disomy (maternal in PWS and paternal in AS) strongly implicate genomic imprinting in this chromosomal region. The principal aim of our group is to apply cytogenetic and molecular biology techniques to perform diagnosis and genetic counselling. Patient studies were usually based on high resolution cytogenetic analysis, quantitative Southern blotting (with D15S9, D15S11, D15S10, D15S12 loci) and dinucleotide repeat polymorphism assay by polymerase chain reaction (PCR) (IR4. 3R and GABARB3). The combination of these different methods allowed us to propose a diagnostic strategy for PWS.     

A patient with both Charcot-Marie-Tooth disease (CMT 1A) and mild spinal muscular atrophy (SMA 3)

In the present study, we report a single Polish SMA family in which the 17p11.2–p12 duplication causative for the Charcot-Marie-Tooth type 1A disease (CMT1A) was found in addition to a deletion of exons 7 and 8 of the SMN1 gene. A patient harboring both SMA and CMT1A mutations manifested with SMA3 phenotype and foot deformity. Her electrophysiological testing showed chronic neurogenic changes in proximal muscles that are typical for SMA, but also slowed conduction velocity in motor and sensory fibers that is typical for demyelinating neuropathy.     

Phonological patterns (templates) in 5p deletion syndrome

ABSTRACT

Whole word phonological patterns (templates) in utterances produced by children with 5p deletion syndrome are analysed, addressing four questions: (1) Are children with 5p deletion syndrome able to generalise over words? (2) How does the template score of children with 5p deletion syndrome relate to those of typically developing children and of the target language? (3) How do the template scores relate to other phonological measures, PCC and consonant variegation? (4) What can the relationship between template scores and phonological measures tell us about templates? Children with 5p deletion syndrome are able to generalise over words, some to a target like extent, others generalise more than expected for their age. The template scores relate to other phonological measures, with two exceptions. The exceptions indicate that the template score of a child with articulatory difficulties may reflect more detailed representations of the words in memory than she is able to express.     

Spectrum of epilepsy in terminal 1p36 deletion syndrome

PURPOSE: Previous reports have summarized the seizures types occurring in 1p36 deletion syndrome. To better define the spectrum of epilepsy, we studied 91 patients (median age 7.8 years) with confirmed 1p36 deletion. METHODS: Based on clinical charts, we retrospectively analyzed the evolution of both the EEG findings and seizures. RESULTS: Epilepsy occurred in 53 patients (58.2%), with onset at a median 2.75 months. First seizures were generalized tonic (8 cases), tonic and clonic (6) or myoclonic (12), simple partial (6), or complex partial (14). Thereafter, 20 patients (21.9%) developed infantile spasms with hypsarrhythmia, at a median age of 5 months. High doses of oral steroids were tried in nine cases, with a prompt remission of seizures in six. Among them, five were seizure-free at the time of evaluation. Conversely, two of three nonresponders to steroids developed severe and refractory epilepsy. At the time of evaluation, 32 patients were seizure-free, from a median age of 1.8 years. Nineteen patients (20.9%) had developed refractory epilepsy with polymorphic seizures, including generalized tonic and tonic-clonic seizures (13) combined with myoclonic seizures (11) and atypical absences (3), atonic seizures (2), or complex partial seizures (3). The EEG showed focal, multifocal or generalized spikes, polyspike, and waves, with poverty of the usual background rhythmic activities. CONCLUSIONS: Early epilepsy is a frequent finding in 1p36 deletion syndrome with infantile spasms as of the most common features that can contribute to a poor clinical outcome. Early diagnosis and management of infantile spasm in this condition is mandatory.     

Characteristics of dystonia in the 18p deletion syndrome,including a new case

Objective of the present study was to evaluate the possible pathophysiology and clinical characteristics of dystonia in patients with the 18p deletion syndrome by describing a new case and reviewing the literature. Dystonia in patients with the 18p deletion syndrome seems to present heterogeneously with a variable age of onset and distribution of symptoms. It may be accompanied with white matter lesions on the MRI. Deletion of 2 known dystonia loci on chromosome 18p, DYT7 and DYT15, or the deletion of another dystonia gene just above the centromere of chromosome 18p may be the cause of dystonia in patients with the 18p deletion syndrome. However, dystonia may also be secondary to structural brain changes often seen in patients with the 18p deletion syndrome.     

12P部分三体的细胞-分子遗传学及表型定位研究

目的 进一步探讨12p部分三体综合征遗传物质增加与临床表现之间的关系.方法 我们对1例具有发育缓慢、精神发育迟滞和面部畸形的13个月大患儿和双亲进行了包括G显带、高分辨和荧光原位杂交(fluorescence in situ hybridization,:FISH)分析,同时对包括文献报道的24例12p部分三体进行表型定位分析.结果 患者的12p部分三体来源于母亲的平衡易位,小睑的发生可能与剂量关系不大,而是12p13区域存在与眼睑发育有关的基因簇,染色体断裂后直接或者间接的影响了他们的表达或功能.导致眼睑发育异常.结论 12p部分三体的典型症状与特定染色体区域的基因表达或功能有关.     

4p- Syndrome: A Chromosomal Disorder Associated with a Particular EEG Pattern

Summary: We report an electroclinical and cytogeneticstudy of 4 patients with Wolf-Hirschhorn syndrome (WHS). In all cases, we observed a stereotyped EEG and clinical picture characterized by generalized or unilateral myoclonic seizures followed later by brief atypical absences. Electrographically, these were accompanied by a sequence of centroparietal or parietotemporal sharp waves; high-voltage wave with a superimposed spike becoming unusual spike-wave complexes, often elicited byeye closure; bursts of diffuse spikes and waves; and frequent jerks. This electroclinical pattern is very similar to the one described in Angelman syndrome (AS) in which a defect in GABA_A receptor function has been suggested. Moreover, the genes encoding the GABA_A receptor subunit have been mapped to the p12–pl3 bands of chromosome 4. Even though the deletion in these cases does not encompass the 4p12–p13 region, we suggest that the electroclinical picture common to WHS and AS might represent a characteristic type of epilepsy linked to a common genetic abnormality.     

Polymicrogyria and infantile spasms in a patient with 1p36 deletion syndrome

A 3-months-old boy presented with partial seizures that soon evolved into infantile spasms. Magnetic resonance imaging revealed bilateral perisylvian polymicrogyria with right-sided predominance. ACTH therapy successfully controlled epilepsy and electroencephalograms were normalized. Conventional G-banded chromosomal analysis was performed due to his distinctive features and a derivative chromosome 1 derived from parental balanced translocation with a karyoptype of 46,XY,der(1)t(1;4)(p36.23;q35) was detected. Fluorescent in situ hybridization analysis confirmed the deleted region of 1p36 as large as 8.6 Mb. This is the first delineation of concurrent complications of infantile spasms and polymicrogyria in patient with 1p36 deletion. 1p36 deletion syndrome should be broadly recognized as a differential diagnosis of regional polymicrogyria and/or infantile spasms.     

Chromosome 1p and 19q status and p53 and p16 expression patterns as prognostic indicators of oligodendroglial tumors: A clinicopathological study using fluorescence in situ hybridization

To verify the prognostic implications of the statuses of chromosome 1p and 19q and the expressions of p53, p16 and GFAP in oligodendrogliomas, we investigated these parameters and correlated the results with patient outcome. Twenty-seven cases of low-grade oligodendroglioma (LO) and 29 cases of anaplastic oligodendroglioma (AO) were analyzed by FISH for 1p and 19q status and by immunohistochemistry for p53, p16, and GFAP expression using a tissue microarray. Direct sequencing of the p53 gene was also performed. 1p deletion was observed in 39 of 56 patients (69.9%), and 19q deletion in 41 of 56 (73.2%). Combined loss of 1p and 19q was found in 38 of 56 (67.9%) and exhibited distinct concomitant deletion (P = 0.000). p53 overexpression was observed in 17 cases (30.3%), GFAP expression in 18 cases (32.1%), and p16 loss in 40 cases (74%) of oligodendrogliomas. The expressions of p53 and GFAP were more frequent in AO than in LO (P = 0.015 and 0.001). In contrast, p53 expression was more common in oligodendrogliomas with an intact 19q (P = 0.029), or an intact 1p (P = 0.071). Only five of 14 patients with p53 expression showed TP53 mutation, which was inversely correlated with 1p deletion (P = 0.036). Patients with combined loss of 1p and 19q exhibited better overall survival (P = 0.045). Patients with p53 expression without combined 1p and 19q loss showed poor overall survival (P < 0.000). However, TP53 mutation along with 1p and 19q status could not predict patient outcome. Patients with p16 loss without combined 1p and 9q loss showed poor overall survival (P = 0.011). Therefore, in oligodendrogliomas, the absence of the combined deletion of 1p and 19q and the aberrant expression of p53 or loss of p16 could be used as poor prognostic markers.     

Involvement of caspase-3 and p38 mitogen-activated protein kinase in cobalt chloride-induced apoptosis in PC12 cells

Our previous study showed that cobalt chloride (CoCl2) could induce PC12 cell apoptosis and that the CoCl2-treated PC12 cells may serve as a simple in vitro model for the study of the mechanism of hypoxia-linked neuronal disorders. The aim of this study is to elucidate the mechanism of CoCl2-induced apoptosis in PC12 cells. Caspases are known to be involved in the apoptosis induced by various stimuli in many cell types. To investigate the involvement of caspases in CoCl2-induced apoptosis in PC12 cells, we generated PC12 cells that stably express the viral caspases inhibitor gene p35 and analyzed the effect of p35 on the process of apoptosis induced by CoCl2. We also examined the effect of cell-permeable peptide inhibitors of caspases. The results showed that the baculovirus p35 gene and the general caspases inhibitor Z-VAD-FMK significantly block apoptosis induced by CoCl2, confirming that caspase is involved in CoCl2-induced apoptosis. Further investigation showed that in this process the caspase-3-like activity is increased, as indicated by the cells' ability to cleave the fluorogenic peptide substrate Ac-Asp-Glu-Val-Asp-7-AMC and to degrade the DNA-repairing enzyme poly-(ADP-ribose) polymerase (PARP), an endogenous caspase-3 substrate. At the same time, caspase-3-specific inhibitors, namely, the peptide Ac-DEVD-CHO, Ac-DEVD-FMK, partially inhibit CoCl2-induced apoptosis. These findings suggested that caspase-3 or caspase-3-like proteases are involved in the apoptosis induced by CoCl2 in PC12 cells. Additionally, we have observed that another apoptotic marker, p38 mitogen-activated protein kinase (MAPK), is significantly activated in this process in a time-dependent manner and that a selective p38 MAPK inhibitor, SB203580, partially inhibits this cell death. The addition of SB203580 also partially suppresses caspase-3-like activity. All these results confirm that the CoCl2-treated PC12 cell is a useful in vitro model with which to study hypoxia-linked neuronal disorders. Furthermore, the results showing that the baculovirus p35 gene and caspase inhibitors possess a remarkable ability to rescue PC12 cells from CoCl2-induced cell death may have implications for future neuroprotective therapeutic approaches for the hypoxia-associated disorders.     

Homozygous deletions of the CDKN2/p16 gene in dural hemangiopericytomas

While most authors currently classify dural-based hemangiopericytoma (HPC) as a distinct entity rather than as a subtype of meningioma, the histogenesis of HPC has long been debated. We have recently shown that meningiomas contain frequent mutations of the neurofibromatosis 2 gene, while HPCs do not, suggesting that HPC is genetically distinct from meningioma. In the present study, we evaluated a series of 31 dural HPCs (including 3 pairs of primary and recurrent tumor) and 26 meningiomas for alterations in the cell-cycle regulatory genes CDKN2/p16 and p53. Homozygous deletions of the CDKN2/p16 gene were detected using a comparative multiplex polymerase chain reaction assay in 7 of 28 primary HPCs (25%), but in only one of 26 meningiomas (P = 0.03). Among the HPCs with recurrence, 1 pair of 3 had a homozygous CDKN2/p16 deletion. The 1 meningioma with a CDKN2/p16 deletion was a meningothelial meningioma, without atypical or malignant features. Single-strand conformational polymorphism analysis of all three exons of CDKN2/p16 and exons 5–8 of p53 revealed no mutations in either HPCs or meningiomas. These results illustrate that homozygous deletions of CDKN2/p16 occur in HPCs and suggest that alterations of the p16-mediated cell-cycle regulatory pathway may underlie the formation or progression of some HPCs. The data also provide further genetic evidence that HPC is not a subtype of meningioma. Received: 26 September 1995 / Revised, accepted: 30 October 1995     

A Girl with Pervasive Developmental Disorder and Complex Chromosome Rearrangement Involving 8p and 10p

We report a 4-year-old girl with a de novo, apparently balanced complex chromosome rearrangement. She initially presented for assessment of velopharyngeal insufficiency due to hypernasal speech. She has distinctive facial features (long face, broad nasal bridge, and protuberant ears with simplified helices), bifid uvula, strabismus, and joint laxity. She is developmentally delayed, with language and cognitive skills approximately 2 SD below the mean expected for her age, and meets ADI, ADOS, and DSM-IV criteria for perva- sive developmental disorder. She has poor eye contact, atypical communication and social interaction, repetitive behaviours and significant difficulties with processing sensory input. Her karyotype is characterized by the presence of two derivative chromosomes; 46,XX, der(8)(10pter->10p12.32::8p12−>8qter), der(10)(8pter->8p21.3::10p12.32−>10p11.23::8 p21.3−> 8p12::10p11.23−>10qter). The der(8) is a result of translocation of the segment 10p12.32−pter onto 8p12. The der(10) has two 8p segments collectively from 8p12-pter in that the segment 8p21.3-pter is translocated onto 10p12.32 and the segment 8p12-p21.3 is inserted at 10p11.23. FISH analysis showed no microdeletion of the major locus at 22q11.2 nor for the minor locus at 10p13p14. This case suggests that aberrations at 8p12, 8p21.3, 10p11.23 and/or 10p12.32 may result in pervasive developmental disorder, associated with mild cognitive delay and specific facial anomalies.     

Chromosomal microarray mapping suggests a role for BSX and Neurogranin in neurocognitive and behavioral defects in the 11q terminal deletion disorder (Jacobsen syndrome)

We performed a prospective analysis on 14 11q- patients to determine the relationship between the degree of cognitive impairment and relative deletion size. Seventeen measures of cognitive function were assessed. All nine patients with a deletion of at least 12.1 Mb had severe global cognitive impairment, with full-scale IQ <50, whereas all five patients with smaller deletions, 相似文献   

HNPP Associated With An Alternatively-Sized Deletion At Chromosome 17p11.2-p12

Chromosome 17p11.2-p12 is prone to unequal crossing-over events associated with inherited neuropathies (17p12) and with forms of mental retardation known as Smith Magenis Syndrome (SMS) (17p11.2). A 1.5 megabase (Mb) duplication or deletion encompassing the PMP22 gene causes respectively Charcot-Marie-Tooth neuropathy type 1A (CMT1A) and Hereditary Neuropathy with liability to Pressure Palsies (HNPP); the unequal crossing over is caused by misalignment of two low-copy repeat elements named CMT1A-REP which flank the duplicated/deleted region. HNPP is genetically homogenous; only exceptional cases have been associated with non-sense mutations of PMP22. In a four-generation pedigree five individuals were affected with a clinically and pathologically typical HNPP (tomaculous neuropathy). PFGE analysis with SacII endonuclease and probe pNEA101, which maps to the proximal CMT1A-REP, failed to detect the 770 and 820 kb junction fragments associated with the 1.5-Mb deletion. Restriction by SacII and NotI showed respectively two novel junction fragments of ≅1.1 and 1.25 Mb, suggesting the presence of a shorter deletion. Nucleotide sequencing of PMP22 was normal. Linkage analysis using the markers D17S1921, D17S839, D17S1357, D17S12, D17S261, D17S953 and D17S1843 confirmed the results of PFGE by demonstrating loss of heterozygosity for D17S1357 and D17S122. The report underlines the high instability of chromosome 17p11.2-p12 and prompts to investigate other mechanisms of genetic rearrangement in that region.     

Hereditary neuropathy with liability to pressure palsies with a small deletion interrupting the PMP22 gene

Hereditary neuropathy with liability to pressure palsies is associated with a deficiency in the Peripheral Myelin Protein 22 (PMP22). Most hereditary neuropathy with liability to pressure palsies cases are caused by a deletion of a 1.5 Mb region on chromosome 17p11.2-12 encompassing the PMP22 gene. We describe a hereditary neuropathy with liability to pressure palsies family that lacks the common deletion, but carries a small deletion spanning the 3' region of the PMP22 gene, causing only a partial deletion of one copy of the gene.     

A new der(1;7)(q10;p10) leading to a singular 1p loss in a case of glioblastoma with oligodendroglioma component

The combined 1p‐/19q‐ deletions in oligodendrogliomas originate from translocation between both chromosomes. In the few cases of oligoastrocytomas and glioblastomas with an oligodendroglioma component (GBMO) where only 1p deletion was described, the origin remains unknown. We report the first case of GBMO, in which a single 1p deletion was detected and was linked to a translocation between chromosomes 1 and 7. Fresh surgical specimens were collected during surgery and the samples were used for cell culture, touch preparation smear slides (TP slides) and DNA extraction. Peripheral venous blood was also collected from the patient. G‐banding using Trypsin and stained with Giemsa (GTG) banding and karyotyping were performed and 1p‐/19q‐, TP53, PTEN and c‐MYC were analyzed by fluorescent in situ hybridization (FISH). Multicolor FISH (mFISH) and microsatellites analyses were also performed to complete the investigation. Three‐dimensional quantitative FISH (3D‐QFISH) of telomeres was performed on nuclei from TP slides and analyzed using TeloView^TM to determine whether the 3D telomere profile as an assessment of telomere dysfunction and a characterization of genomic instability could predict the disease aggressiveness. An unbalanced chromosomal translocation was found in all metaphases and confirmed by mFISH. The karyotype of the case is: 50～99,XXX, +der(1;7)(q10;p10),inc[47] The derivative chromosome was found in all 47 analyzed cells, but the number of derivatives varied from one to four. There was neither imbalance in copy number for genes TP53 and PTEN, nor amplification of c‐MYC gene. We did not find loss of heterozygosity with analysis of microsatellite markers for chromosomes 1p and 19q in tumor cells. The 3D‐telomere profile predicted a very poor prognostic and short‐term survival of the patient and highlights the potential clinical power of telomere signatures as a solid biomarker of GBMO. Furthermore, this translocation between chromosomes 1 and 7 led to a singular 1p deletion in this GBMO and may generate the 1p and 7q deletions.     

Myoclonic Absence-Like Seizures and Chromosome Abnormality Syndromes

Summary: Purpose: We explored the relationship between myoclonic absence seizures (MAS) and underlying chromosome disorders.
Methods: Among 14 patients with MAS observed in three centers, 5 had typical cryptogenic myoclonic absence epilepsy (MAE), 2 had MAS associated with other seizure types (1 with signs of a neuronal migration abnormality and 1 with signs of a metabolic disorder), and 7 had MAS, with or without other seizure types, complicating a chromosome abnormality syndrome-2 with trisomy 12p, 4 with Angelman syndrome, and 1 with inv dup (15).
Results: In the 7 patients with chromosomopathy, MAS appeared at a mean age of 2.9 years (range 4 months to 6 years 6 months), had a duration of 4–20 s, and were accompanied by reduced awareness and rhythmic myoclonic jerks involving proximal limb muscles. Ictal EEG showed 2- to 3-Hz generalized spike-and-wave discharges.
Conclusions: In these patients, MAS differed slightly from those of typical MAE: age of onset was earlier, absences were of shorter duration, and no clear increase in muscular tone was noted. Abnormal expression of genes codifying for the subfamily of K⁺ channels and for γ-aminobutyric acid-3 subunit receptors (GABRBS), both located in the chromosome segments involved in the chromosomopathies presented by our patients, could be responsible for the same generalized seizure type. Chromosome analysis should be performed in patients with mental retardation and MAS, especially when the ictal pattern does not completely overlap that observed in MAE.     

H2O2预处理通过ERK1/2和p38 MAPK信号通路上调14-3-3蛋白在PC12

OBJECTIVE: To investigate the protective effects of hydrogen peroxide preconditioning (HPP) on the pheochromocytoma (PC12) cells treated with 1-methyl-4-phenylpyridinium (MPP(+)) and to explore the potential mechanisms. METHODS: The viability and apoptosis of PC12 cells were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and 4',6'-diamidino-2-phenylindole (DAPI) staining, respectively. The expressions of 14-3-3 protein and phosphorylated p38 mitogen-activated protein kinase (MAPK) were determined by Western blot. Enzyme-linked immunosorbent assay (ELISA) was used to measure the activity of extracellular signal-regulated protein kinase 1/2 (ERK1/2). RESULTS: The cell viability decreased and the number of apoptotic cells increased dramatically in MPP(+) group compared with that in Control group. HPP induced a significant increase in cell viability and a marked decrease in population of apoptotic cells of the MPP(+)-treated PC12 cells, accompanied with up-regulation of 14-3-3 protein and increase of ERK1/2 and p38 MAPK activities. The 14-3-3 protein expression was positively correlated with the phosphorylation of ERK1/2. Furthermore, inhibition of the ERK1/2 with PD98059 abolished the 14-3-3 protein up-regulation in PC12 cells induced by HPP. CONCLUSION: HPP protects PC12 cells against MPP(+) toxicity by up-regulating 14-3-3 protein expression through the ERK1/2 and p38 MAPK signaling pathways.