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1.
Proc Natl Acad Sci U S A ; 116(17): 8261-8268, 2019 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-30962370

RESUMO

Proactive policing, the strategic targeting of people or places to prevent crimes, is a well-studied tactic that is ubiquitous in modern law enforcement. A 2017 National Academies of Sciences report reviewed existing literature, entrenched in deterrence theory, and found evidence that proactive policing strategies can reduce crime. The existing literature, however, does not explore what the short and long-term effects of police contact are for young people who are subjected to high rates of contact with law enforcement as a result of proactive policing. Using four waves of longitudinal survey data from a sample of predominantly black and Latino boys in ninth and tenth grades, we find that adolescent boys who are stopped by police report more frequent engagement in delinquent behavior 6, 12, and 18 months later, independent of prior delinquency, a finding that is consistent with labeling and life course theories. We also find that psychological distress partially mediates this relationship, consistent with the often stated, but rarely measured, mechanism for adolescent criminality hypothesized by general strain theory. These findings advance the scientific understanding of crime and adolescent development while also raising policy questions about the efficacy of routine police stops of black and Latino youth. Police stops predict decrements in adolescents' psychological well-being and may unintentionally increase their engagement in criminal behavior.


Assuntos
Negro ou Afro-Americano , Hispânico ou Latino , Delinquência Juvenil , Polícia/psicologia , Estresse Psicológico , Adolescente , Negro ou Afro-Americano/psicologia , Negro ou Afro-Americano/estatística & dados numéricos , Hispânico ou Latino/psicologia , Hispânico ou Latino/estatística & dados numéricos , Humanos , Delinquência Juvenil/psicologia , Delinquência Juvenil/estatística & dados numéricos , Aplicação da Lei , Estudos Longitudinais , Masculino , Estresse Psicológico/epidemiologia , Estresse Psicológico/psicologia
2.
Genet Med ; 15(1): 3-13, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22935720

RESUMO

PURPOSE: A small supernumerary marker chromosome is often seen in patients with developmental disorders. Prior to array-based comparative genomic hybridization markers were rarely genotyped end to end. In this study, a valid genotype-to-phenotype correlation was possible because the supernumerary marker chromosomes were fully characterized by array-based comparative genomic hybridization in a genome-wide analysis. METHODS: Ten consecutive de novo small supernumerary marker chromosome cases were systematically genotyped using G-banding, C-banding, AgNOR staining, whole-genome array-based comparative genomic hybridization, and fluorescence in situ hybridization. RESULTS: Among 10 small supernumerary marker chromosome cases studied, 4 (40%) were not identified by array-based comparative genomic hybridization because of low-level mosaicism or because they lacked euchromatin. One case (10%) was a simple pericentromeric marker extending from 5p13.3 to 5q11.2. Five (50%) markers showed unexpected complexity. Two cases had markers that were derivative acrocentric (AgNOR+) chromosomes with the euchromatin from chromosomes 18p or 19p. Each of the other three cases with complex markers had unusual characteristics including a marker from noncontiguous segments of chromosome 19q, a highly complex rearrangement involving a chromosome 20 homolog as well as the small supernumerary marker chromosome, and a mosaic duplication of a proximal 8p marker. CONCLUSION: Small supernumerary marker chromosomes are frequently complex on the basis of our small sample. Whole-genome array-based comparative genomic hybridization characterization of the small supernumerary marker chromosome provided informed genetic counseling.


Assuntos
Aberrações Cromossômicas , Hibridização Genômica Comparativa , Marcadores Genéticos , Humanos , Hibridização in Situ Fluorescente , Cariotipagem , Mosaicismo , Polimorfismo de Nucleotídeo Único
3.
Am J Med Genet A ; 152A(11): 2924-36, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20979197

RESUMO

Jumping translocations (JTs) are rare constitutional or acquired rearrangements involving a donor and several receiver chromosomes. They may be inherited or de novo. JTs can be found as a cultural artifact, in normal individuals or in pathological conditions. The clinical consequences range from spontaneous abortion, loss of fetus, chromosome syndrome, congenital abnormalities, and infertility to malignancy. Considering the breakpoints of JTs, they are localized predominantly in repeat regions such as pericentromeric, centromeric, subtelomeric, telomeric, and occasionally interstitial regions that may be in a low copy repeats (LCR) or in a telomere like sequence. Differences between the constitutional and acquired JTs donor breakpoints suggest an independent mechanism in their formation. In this review, a new JT involving a donor chromosome 18p10qter and recipients 17q25qter or 1q25qter found by CVS of a twin pregnancy is described. This case illustrates the diagnostic challenges posed by JTs.In this study, our knowledge on JTs is consolidated to improve identification, management, and counseling.


Assuntos
Amostra da Vilosidade Coriônica/métodos , Translocação Genética , Gêmeos/genética , Adulto , Desenvolvimento Embrionário , Feminino , Humanos , Hibridização in Situ Fluorescente , Sequências Repetitivas Dispersas/genética , Cariotipagem , Gravidez
4.
Front Immunol ; 10: 1964, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31497017

RESUMO

Primary immunodeficiency (PID) refers to a group of heterogeneous genetic disorders with a weakened immune system. Mendelian susceptibility to mycobacterial disease (MSMD) is a subset of PID in which patients exhibit defects in intrinsic and innate immunity. It is a rare congenital disorder characterized by severe and recurrent infections caused by weakly virulent mycobacteria or other environmental mycobacteria. Any delay in definitive diagnosis poses a major concern due to the confounding nature of infections and immune deficiencies. Here, we report the clinical, immunological, and genetic characteristics of two siblings (infants) with recurrent infections. There was a history of death of two other siblings in the family after BCG vaccination. Whole exome sequencing of the two affected surviving infants along with their consanguineous parents identified a novel, homozygous single nucleotide splice acceptor site variant in intron 2 of the interferon gamma receptor 2 (IFNGR2) gene. Sanger sequencing of DNA obtained from blood and fibroblasts confirmed the variant. The patients underwent bone marrow transplantation from their father as a donor. RT-PCR and Sanger sequencing of the cDNA of patients from blood samples after transplantation showed the expression of both wild type and mutant transcript expression of IFNGR2. To assess partial or complete expression of IFNGR2 mutant transcripts, fibroblasts were cultured from skin biopsies. RT-PCR and Sanger sequencing of cDNA obtained from patient fibroblasts revealed complete expression of mutant allele and acquisition of a cryptic splice acceptor site in exon 3 that resulted in deletion of 9 nucleotides in exon 3. This led to an in-frame deletion of three amino acids p.(Thr70-Ser72) located in a fibronectin type III (FN3) domain in the extracellular region of IFNGR2. This illustrates individualized medicine enabled by next generation sequencing as identification of this mutation helped in the clinical diagnosis of MSMD in the infants as well as in choosing the most appropriate therapeutic option.


Assuntos
Predisposição Genética para Doença , Síndromes de Imunodeficiência/genética , Infecções por Mycobacterium/genética , Receptores de Interferon/genética , Humanos , Lactente , Masculino , Mutação , Sítios de Splice de RNA
5.
J Clin Endocrinol Metab ; 104(8): 3539-3544, 2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31125088

RESUMO

CONTEXT: Inactivating germline mutations in the aryl hydrocarbon receptor interacting protein (AIP) gene are linked to pituitary adenoma predisposition. Here, we present the youngest known patient with AIP-related pituitary adenoma. CASE DESCRIPTION: The patient presented at the age of 4 years with pituitary apoplexy and left ptosis with severe visual loss following a 1-year history of abdominal pain, headaches, and rapid growth. His IGF-1 level was 5× the upper limit of normal, and his random GH level was 1200 ng/mL. MRI showed a 43 × 24 × 35‒mm adenoma with suprasellar extension invading the left cavernous sinus (Knosp grade 4). After transsphenoidal surgery, histology showed a grade 2A sparsely granulated somatotropinoma with negative O6-methylguanine-DNA methyltransferase and positive vascular endothelial growth factor staining. Genetic testing identified a heterozygous germline nonsense AIP mutation (p.Arg81Ter). Exome sequencing of the tumor revealed that it had lost the entire maternal chromosome-11, rendering it hemizygous for chromosome-11 and therefore lacking functional copies of AIP in the tumor. He was started on octreotide, but because the tumor rapidly regrew and IGF-1 levels were unchanged, temozolomide was initiated, and intensity-modulated radiotherapy was administered 5 months after surgery. Two months later, bevacizumab was added, resulting in excellent tumor response. Although these treatments stabilized tumor growth over 4 years, IGF-1 was normalized only after pegvisomant treatment, although access to this medication was intermittent. At 3.5 years of follow-up, gamma knife treatment was administered, and pegvisomant dose increase was indicated. CONCLUSION: Multimodal treatment with surgery, long-acting octreotide, radiotherapy, temozolomide, bevacizumab, and pegvisomant can control genetically driven, aggressive, childhood-onset somatotropinomas.


Assuntos
Adenoma/genética , Adenoma/terapia , Peptídeos e Proteínas de Sinalização Intracelular/genética , Neoplasias Hipofisárias/genética , Neoplasias Hipofisárias/terapia , Protocolos Antineoplásicos , Bevacizumab/uso terapêutico , Pré-Escolar , Terapia Combinada , Hormônio do Crescimento Humano/análogos & derivados , Hormônio do Crescimento Humano/uso terapêutico , Humanos , Masculino , Mutação , Octreotida/uso terapêutico , Hipófise/cirurgia , Radioterapia Adjuvante , Temozolomida/uso terapêutico
7.
Indian J Ophthalmol ; 64(12): 924-929, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28112135

RESUMO

PURPOSE: This study aims to describe the phenotype and genotype of two Indian families affected with X-linked choroideremia (CHM). MATERIALS AND METHODS: In these two families, the affected individuals and unaffected family members underwent a comprehensive ophthalmic examination including an optical coherence tomography (OCT) and electroretinogram. Blood samples were collected from the families for genetic analysis. Next generation sequencing (NGS) was done using a panel of 184 genes, which covered previously associated genes with retinal dystrophies. Sequencing data were analyzed for the CHM, RPGR, and RP2 genes that have been implicated in CHM and X-linked retinitis pigmentosa (XLRP), respectively. The identified variants were confirmed by Sanger sequencing in available individuals and unrelated controls. RESULTS: In two unrelated male patients, NGS analysis revealed a previously reported 3'-splice site change c.820-1G>C in the CHM gene in the first family and hemizygous mutation c.653G>C (p.Ser218X) in the second family. The asymptomatic family members were carriers for these mutations. Spectral domain-OCT showed loss of outer retina, preservation of the inner retina, and choroidal thinning in the affected males and retinal pigment epithelial changes in the asymptomatic carriers. The identified mutations were not present in 100 controls of Indian origin. There were no potential mutations found in XLRP-associated (RPGR and RP2) genes. CONCLUSION: This report describes the genotype and phenotype findings in patients with CHM from India. The identified genetic mutation leads to lack of Rab escort protein-1 (REP-1) or affects the production of a REP-1 protein that is likely to cause retinal abnormalities in patients.


Assuntos
Coroideremia/genética , Proteínas do Olho/genética , Testes Genéticos/métodos , Mutação , Adulto , Coroideremia/diagnóstico , Coroideremia/metabolismo , Análise Mutacional de DNA , Eletrorretinografia , Proteínas do Olho/metabolismo , Feminino , Angiofluoresceinografia , Fundo de Olho , Genótipo , Humanos , Índia , Masculino , Linhagem , Fenótipo
8.
BMC Med Genet ; 6: 3, 2005 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-15655077

RESUMO

BACKGROUND: Autism is a behavioral disorder with impaired social interaction, communication, and repetitive and stereotypic behaviors. About 5-10 % of individuals with autism have 'secondary' autism in which an environmental agent, chromosome abnormality, or single gene disorder can be identified. Ninety percent have idiopathic autism and a major gene has not yet been identified. We have assessed the incidence of chromosome abnormalities and Fragile X syndrome in a population of autistic patients referred to our laboratory. METHODS: Data was analyzed from 433 patients with autistic traits tested using chromosome analysis and/or fluorescence in situ hybridization (FISH) and/or molecular testing for fragile X syndrome by Southern and PCR methods. RESULTS: The median age was 4 years. Sex ratio was 4.5 males to 1 female [354:79]. A chromosome (cs) abnormality was found in 14/421 [3.33 %] cases. The aberrations were: 4/14 [28%] supernumerary markers; 4/14 [28%] deletions; 1/14 [7%] duplication; 3/14 [21%] inversions; 2/14 [14%] translocations. FISH was performed on 23 cases for reasons other than to characterize a previously identified cytogenetic abnormality. All 23 cases were negative. Fragile-X testing by Southern blots and PCR analysis found 7/316 [2.2 %] with an abnormal result. The mutations detected were: a full mutation (fM) and abnormal methylation in 3 [43 %], mosaic mutations with partial methylation of variable clinical significance in 3 [43%] and a permutation carrier [14%]. The frequency of chromosome and fragile-X abnormalities appears to be within the range in reported surveys (cs 4.8-1.7%, FRAX 2-4%). Limitations of our retrospective study include paucity of behavioral diagnostic information, and a specific clinical criterion for testing. CONCLUSIONS: Twenty-eight percent of chromosome abnormalities detected in our study were subtle; therefore a high resolution cytogenetic study with a scrutiny of 15q11.2q13, 2q37 and Xp23.3 region should be standard practice when the indication is autism. The higher incidence of mosaic fragile-X mutations with partial methylation compared to FRAXA positive population [50% vs 15-40%] suggests that faint bands and variations in the Southern band pattern may occur in autistic patients.


Assuntos
Transtorno Autístico/epidemiologia , Transtorno Autístico/genética , Aberrações Cromossômicas/estatística & dados numéricos , Análise Citogenética/métodos , Síndrome do Cromossomo X Frágil/genética , Pré-Escolar , Feminino , Proteína do X Frágil da Deficiência Intelectual , Humanos , Masculino , Epidemiologia Molecular/métodos , Mutação/genética , Proteínas do Tecido Nervoso/genética , Proteínas de Ligação a RNA/genética
9.
Cancer Genet Cytogenet ; 157(1): 70-3, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15676151

RESUMO

A recurring translocation (X;20)(q13;q13) was found in four women ranging in age from 57 to 77 years. They had myelodysplasia, myelodysplasia with thrombocytopenia and pancytopenia, transforming to myelofibrosis, and myelodysplasia with sideroblastic anemia, respectively. The t(X;20) was the sole abnormality in three cases; one case also had a der(1;7)(q10;p10). Added to three previously reported cases, our four cases bring the total to seven; thus, t(X;20)(q13;q13) is a nonrandom translocation associated with myeloid disorders. Previous FISH studies showed that the breakpoint on the X is proximal to XIST. In one of our cases, the breakpoint on the X was shown to be proximal to Xq12, by FISH using a probe for the androgen receptor gene locus.


Assuntos
Cromossomos Humanos Par 20 , Cromossomos Humanos X , Síndromes Mielodisplásicas/genética , Translocação Genética , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Pancitopenia/genética , Mielofibrose Primária/genética
11.
J Exp Soc Psychol ; 49(4): 732-740, 2013 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-23687385

RESUMO

An experimental study tests if people's hostility after experiencing rejection is partly explained by the degree to which they had initially suppressed their own feelings and beliefs to please the source of rejection. This hypothesis emerges from the literatures on women's self-silencing and that on rejection-sensitivity, which has documented that rejection-sensitive women show strong responses to rejection, but are also likely to self-silence to please their partners. An online dating paradigm examined if this self-silencing drives post-rejection hostility among women. Participants were given the opportunity to read about a potential dating partner before meeting that person, and were randomly assigned to one of 3 experimental conditions that resulted in rejection from the potential date or from another dater. Self-silencing was captured as the suppression of tastes and opinions that clashed with those of the prospective partner. Self-silencing moderated the effect of rejection on hostility: Self-silencing to the prospective partner was associated with greater post-rejection hostility among women, but not men. Self-silencing to someone other than the rejecter was not predictive of hostility. Women's dispositional rejection-sensitivity predicted greater hostility after rejection, and self-silencing mediated this association. Efforts to secure acceptance through accommodation may help explain the paradoxical tendency of some people to show strong rejection-induced hostility toward those whose acceptance they have sought.

12.
J Pers Soc Psychol ; 99(5): 802-23, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20649367

RESUMO

Societies and social scientists have long held the belief that exclusion induces ingratiation and conformity, an idea in contradiction to robust empirical evidence linking rejection with hostility and aggression. The classic literatures on ingratiation and conformity help resolve this contradiction by identifying circumstances under which rejection may trigger efforts to ingratiate. Jointly, findings from these literatures suggest that when people are given an opportunity to impress their rejecters, ingratiation is likely after rejection experiences that are harsh and that occur in important situations that threaten the individual's self-definition. Four studies tested the hypothesis that people high in rejection sensitivity and therefore dispositionally concerned about rejection will utilize opportunities to ingratiate after harsh rejection in situations that are self-defining. In 3 studies of situations that are particularly self-defining for men, rejection predicted ingratiation among men (but not women) who were high in rejection sensitivity. In a 4th study, harsh rejection in a situation particularly self-defining for women predicted ingratiation among highly rejection-sensitive women (but not men). These findings help identify the specific circumstances under which people are willing to act in socially desirable ways toward those who have rejected them harshly.


Assuntos
Rejeição em Psicologia , Conformidade Social , Comportamento , Feminino , Doações , Processos Grupais , Hostilidade , Humanos , Masculino , Motivação , Grupo Associado , Fatores Sexuais , Inquéritos e Questionários , Adulto Jovem
13.
Cancer Genet Cytogenet ; 184(2): 77-86, 2008 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-18617055

RESUMO

This study assessed the efficacy of FISH for detecting 1p/19q deletion in gliomas on 77 paraffin-embedded tissue samples, of which 42 cases (55%) were positive for 1p/19q codeletion; 7 of the 42 had a previous history of glioma. In one case, analysis failed. The remaining 34 cases were negative; of these, three had a previous history of glioma and one had the reverse 1q/19p deletion. A majority of the 10 recurrent gliomas had progressed, and 70% had a 1p/19q deletion. The signal pattern in a majority of 1p/19q codeletion cases was a single red marker signal and two green reference signals (1R2G) for both probe sets. One case had a different signal pattern for chromosomes 1 and 19 (1R2G and 2R4G), as seen in polysomy cells. Three cases had two target and four control signals (2R4G), as seen in tetraploid cells. Eleven had complex signal patterns seen in diploid and polyploid cells (1R2G/

Assuntos
Neoplasias Encefálicas/genética , Deleção Cromossômica , Cromossomos Humanos Par 19 , Cromossomos Humanos Par 1 , Glioma/genética , Hibridização in Situ Fluorescente/métodos , Adulto , Idoso , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/diagnóstico , Estudos de Coortes , Feminino , Glioma/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
14.
Cancer Genet Cytogenet ; 183(1): 1-5, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18474289

RESUMO

A validation of fluorescence in situ hybridization (FISH) assays for paraffin-embedded tissues (PET) is required before clinical use. Although the FISH probe validation process for hematologic disorders has been described during recent years, none of these descriptions, to our knowledge, address the validation process for paraffin-embedded tissues in detail. We describe an applicable preclinical validation process. The following five-step validation is outlined: (1) pathologist's review of slide; (2) probe validation on metaphases to assess sensitivity and specificity; (3) a pilot study using FISH probes on PET; (4) analytical validation using normal and abnormal PET samples to establish a normal reference range or cutoff; and (5) application of the cutoffs to test samples. Although the procedure focuses on dual-color, dual-fusion FISH assays, the same steps could be used for any type of probe. We have described a preclinical validation for probes on paraffin-embedded tissue.


Assuntos
Corantes Fluorescentes , Doenças Hematológicas/diagnóstico , Doenças Hematológicas/patologia , Hibridização in Situ Fluorescente/métodos , Inclusão em Parafina , Corantes Fluorescentes/farmacologia , Doenças Hematológicas/genética , Humanos , Cariotipagem , Metáfase , Projetos Piloto , Sensibilidade e Especificidade
15.
Am J Med Genet A ; 117A(3): 261-7, 2003 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-12599190

RESUMO

In this study, we report two cases each with a complex chromosome rearrangement concealing a submicroscopic terminal deletion. The first case had a mos 46,XX,der(1)t(1;9)(p36.3;p13). ish der(1)(wcp9 +, 1ptel-, 9ptel +, pan tel +)[88]/46,XX. ish del(1)(1ptel -, 9ptel -, pan tel +)[12] karyotype. Scrutiny by FISH using wcp 9, 1ptel, 9ptel, and pan telomeric probes found a subtelomeric 1ptel deletion on the der(1) in the abnormal cell line and on a chromosome 1 in the apparently normal cell line. The telomere (TTAGGG)n, however, was present on the terminal ends of both copies of chromosome 1 in the apparently normal and abnormal cell lines. The second case had a de novo mos 46,X,der(X)t(X;22)(p22.3;q11.2),inv dup(22)(q11.2).ish der(X)(wcpX +,wcp22 +,KAL +, STS -,Xptel -,BCR +),inv dup(22)(wcp22 +,TUPLE ++,BCR -)[85]/45,X,der(X)t(X;22)(p22.3;q11.2),- 22[15].ish der(X)(wcpX +,wcp22 +, KAL +,STS -,Xptel -,BCR +) karyotype. FISH probes identified a terminal Xpter deletion, distal to the KAL gene. The two rearrangements are hypothesized to have been initiated by a terminal deletion. We propose a model for the formation of the rearrangement in Case 1, which invokes independent telomere stabilization of the sister chromatids. A terminal deletion 1pter in meiosis, was followed by acquiring or regenerating a telomere (TTAGGG)n cap on one chromatid and the other chromatid was involved in a translocation with a chromosome 9 chromatid. Following segregation of this chromosome the viable cell line survives to form the mosaic karyotype. Our findings suggest that subtelomeric deletions should be ruled out in cases with complex and simple rearrangements involving the terminal regions.


Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 1/genética , Cromossomos Humanos X/genética , Translocação Genética , Cromátides/genética , Feminino , Feto/metabolismo , Humanos , Hibridização in Situ Fluorescente , Lactente , Cariotipagem , Modelos Genéticos , Telômero/genética
16.
Am J Med Genet A ; 118A(2): 156-71, 2003 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-12655496

RESUMO

A 7-month-old boy with developmental delay and congenital abnormalities and a 58-year-old man with mental retardation, impaired speech, and dysmorphic features were referred for cytogenetic studies. The peripheral blood chromosome studies of Patient 1 had a de novo mosaic karyotype with 2-6 supernumerary marker chromosomes. Patient 2 had a mosaic karyotype with 1-5 supernumerary marker chromosomes and normal cells. All markers appeared to have a centromere by C-banding and also by fluorescence in situ hybridization (FISH) using all centromere probe for Patient 1. The majority of the markers appeared like rings. Except for one marker in Patient 1 and 2-3 markers in Patient 2 with discernible >5 Mb euchromatin, the rest of the markers were minute and some appeared to have barely discernible euchromatin in C-banding or FISH. Spectral karyotyping (SKY) was attempted to determine the origin of the marker chromosomes. Because some markers had barely any euchromatin, their classification was not clear cut and they were identified as derived from more than one chromosome. The SKY classification of the markers in Patient 1 was 1, 3, 5, 7, 11, 15, and 22 and in Patient 2 was 1, 5, 6, or 7. Patient 2 was lost to further follow-up studies. To confirm the recurring SKY classifications in Patient 1, centromere probes for chromosomes 1, 3, 5, 7, 11, 15, and 22 were used. The markers were negative for 1, 3, and 11 but positive for 7, 15, and 22 and probably 5. Since 5 centromere probe cross hybridizes with 1 and 19, the weak signal on the marker/s in successive hybridization did not give a definitive answer. Also, the 5 paint probe was not conclusive because of the minute size of the marker. In some metaphases, two markers were derived from 5 or 22. For clinical considerations, the marker derived from 7, although variable in size, appeared to consistently have euchromatin, followed by 15, while 22 and 5 markers were mostly centromeric heterochromatin. The elastin gene probe that maps to 7q11.23, SNRPN gene that maps to 15q11.2, and TUPLE gene that maps to 22q11.2 did not give a signal on the markers. As expected for a majority of ring chromosomes, the pan telomere probe did not hybridize to any of the markers. This highly unusual karyotype was confirmed in the buccal epithelium using a mix of centromere 7 and 15 probes and the combination 14/22 probe. The ratio of additional FISH signals in the buccal mucosal cells was comparable to the ratios observed in the peripheral blood. In this study, we have attempted to consolidate the data on >/=2 marker cases to understand the analysis constraints, the range of clinical abnormalities, and the mechanisms involved. The literature was surveyed for multiple markers cases. A majority of the reported cases had two markers, either derived from the same chromosome or from two different chromosomes or two cell lines with different markers derived from the same chromosome. Cases with three or more markers were rare. The nature and extent of euchromatin content of the multiple markers appears to determine the phenotype. Frequently, multiple marker cases had small to minute markers. The clinical presentation varied from mild to severe. While two bisatellited markers may be associated with infertility, the phenotype in other cases ranged from borderline intelligence and mild dysmorphism to developmental delay, mental retardation, and congenital abnormalities.


Assuntos
Aneuploidia , Cromossomos em Anel , Bandeamento Cromossômico , Cromossomos Humanos Par 22/genética , Cromossomos Humanos Par 5/genética , Cromossomos Humanos Par 7/genética , Humanos , Hibridização in Situ Fluorescente , Lactente , Cariotipagem/métodos , Masculino , Pessoa de Meia-Idade , Trissomia
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