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1.
Clin Genet ; 93(6): 1240-1244, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29493781

RESUMO

Paget's disease of bone (PDB) is a skeletal disorder whose molecular basis is not fully elucidated. However, 10% of patients show a familial PDB and 35% of them carry mutations in the SQSTM1 gene. We recently reported a founder mutation (p.Pro937Arg) in the ZNF687 gene, underlying PDB complicated by giant cell tumor (GCT/PDB) and rarely occurring in PDB patients without neoplastic degeneration. Since 80% of Italian GCT/PDB patients derive from Avellino, we hypothesized that ZNF687 mutation rate was higher in this region than elsewhere. Interestingly, our molecular analysis on 30 PDB patients showed that 33% hosted ZNF687 mutations, with the p.Pro937Arg identified in 8 familial cases. Two novel ZNF687 mutations (p.Pro665Leu and p.Gln784Glu) were detected in 2 sporadic patients. Only 2 subjects were positive for the p.Pro392Leu mutation in SQSTM1. ZNF687-mutated patients showed a severe PDB, with a remarkable number of affected sites. in vitro studies revealed that the ZNF687-mutant osteoclasts appeared as giant sized with up to 150 nuclei, never described in PDB. Finally, we also confirmed the causality of the p.Pro937Arg mutation in 4 additional GCT/PDB cases deriving from the same geographic area, indicating that PDB and GCT/PDB represent 2 sides of the same coin.


Assuntos
Proteínas de Ligação a DNA/genética , Mutação/genética , Osteíte Deformante/genética , Fatores de Transcrição/genética , Sequência de Aminoácidos , Sequência de Bases , Diferenciação Celular , Feminino , Geografia , Tumores de Células Gigantes/genética , Humanos , Itália , Masculino , Osteoclastos/patologia , Linhagem , Proteína Sequestossoma-1/genética , Fatores de Transcrição/química , Fatores de Transcrição/metabolismo
2.
Clin Genet ; 93(5): 982-991, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29364500

RESUMO

We recently described a complex multisystem syndrome in which mild-moderate myopia segregated as an independent trait. A plethora of genes has been related to sporadic and familial myopia. More recently, in Chinese patients severe myopia (MYP25, OMIM:617238) has been linked to mutations in P4HA2 gene. Seven family members complaining of reduced distance vision especially at dusk underwent complete ophthalmological examination. Whole-exome sequencing was performed to identify the gene responsible for myopia in the pedigree. Moderate myopia was diagnosed in the family which was associated to the novel missense variant c.1147A > G p.(Lys383Glu) in the prolyl 4-hydroxylase,alpha-polypeptide 2 (P4HA2) gene, which catalyzes the formation of 4-hydroxyproline residues in the collagen strands. In vitro studies demonstrated P4HA2 mRNA and protein reduced expression level as well as decreased collagen hydroxylation and deposition in mutated fibroblast primary cultures compared to healthy cell lines. This study suggests that P4HA2 mutations may lead to myopic axial elongation of eyeball as a consequence of quantitative and structural alterations of collagen. This is the first confirmatory study which associates a novel dominant missense variant in P4HA2 with myopia in Caucasian patients. Further studies in larger cohorts are advisable to fully clarify genotype-phenotype correlations.


Assuntos
Colágeno/genética , Hidroxilação/genética , Miopia/genética , Prolil Hidroxilases/genética , Adolescente , Adulto , Criança , China/epidemiologia , Colágeno/metabolismo , Exoma/genética , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Mutação de Sentido Incorreto/genética , Miopia/epidemiologia , Miopia/patologia , Linhagem , Fenótipo , Adulto Jovem
3.
J Steroid Biochem Mol Biol ; 154: 267-73, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26344639

RESUMO

The harderian gland (HG) is an orbital gland of the vast majority of land vertebrates. In the Syrian hamster these glands display a marked sexual dimorphism. Here we present data on a male specific clone named MHG30. The MHG30 cDNA (1470 bp) has significant sequence homologies with human #15µ10#Δ6-desaturase enzymes. The expression of MHG30 has been found in male HG and in the liver of both sexes, no other tissue showing the presence of MHG30 mRNA. Castration brings the MHG30 levels below detectable level in about 7 days. In in vitro cultures of male hamster HG cells, androgens (A) determine an enhancement of MHG30 expression in a time-dependent manner. Conversely, a continuous decrement has been observed in control cells and in cells treated with A plus flutamide (F) or with A and cycloheximide (Cy). Incubation of cells in cultures supplemented with desamethason (Dex) or thyroid hormone (T3) also increases MHG30 expression while 17ß-estradiol prevents the stimulatory effect exerted by A, Dex and T3. Findings strongly suggest that the MHG30 gene could be involved in supporting the sexual dimorphism and its expression is likely triggered by a series of hormonal interactions.


Assuntos
Ácidos Graxos Dessaturases/genética , Regulação Enzimológica da Expressão Gênica/fisiologia , Glândula de Harder/enzimologia , Hormônios/fisiologia , Animais , Sequência de Bases , Castração , Cricetinae , DNA Complementar , Masculino , Mesocricetus , Dados de Sequência Molecular
4.
Science ; 350(6256): 64-7, 2015 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-26272904

RESUMO

Directly detecting thermal emission from young extrasolar planets allows measurement of their atmospheric compositions and luminosities, which are influenced by their formation mechanisms. Using the Gemini Planet Imager, we discovered a planet orbiting the ~20-million-year-old star 51 Eridani at a projected separation of 13 astronomical units. Near-infrared observations show a spectrum with strong methane and water-vapor absorption. Modeling of the spectra and photometry yields a luminosity (normalized by the luminosity of the Sun) of 1.6 to 4.0 × 10(-6) and an effective temperature of 600 to 750 kelvin. For this age and luminosity, "hot-start" formation models indicate a mass twice that of Jupiter. This planet also has a sufficiently low luminosity to be consistent with the "cold-start" core-accretion process that may have formed Jupiter.

5.
Hernia ; 19(2): 273-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25337870

RESUMO

PURPOSE: There is a significant morbidity associated with abdominal wall reconstruction (AWR) with a need for overall improvement during the post-operative management. Scientific literature has proven the use of negative pressure therapy (NPT) in wound healing for orthopedic and cardiac surgery with limited data present on its role in AWR. The goal of this study was to examine whether primary wound events were different between patients who had primary closure with NPT versus patients who only had primary closure after AWR. METHODS: This retrospective study examined the rate of post-operative complications in all open-complex AWR that were done in a similar fashion between May 2008 and July 2011 at two large university teaching hospitals. Wound closure was stringent upon attending surgeon preference without randomization. RESULTS: There were a total of 61 patients who met inclusion criteria with an average age of 54 and 60 % were women. Thirty-two patients had primary closure and 29 patients had primary closure with NPT. The mean length of follow-up was 167 days for both groups. The type of wound closure had an effect on the rate of hernia recurrence and surgical site infections. The application of NPT leads to lower hernia recurrence rate of 25 versus 3% and the type of wound closure had a profound effect on the rate and type of SSI. CONCLUSIONS: The data presented in this study demonstrates a potential advantage for adjunctive NPT in patients undergoing AWR. There is an associated decreased incidence in the overall rate of SSI and hernia recurrence with the use of NPT in those patients undergoing AWR. These results show an advantage for adjunctive NPT.


Assuntos
Parede Abdominal/cirurgia , Técnicas de Fechamento de Ferimentos Abdominais , Hérnia Ventral/cirurgia , Tratamento de Ferimentos com Pressão Negativa , Infecção da Ferida Cirúrgica/prevenção & controle , Feminino , Hérnia Ventral/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Telas Cirúrgicas , Infecção da Ferida Cirúrgica/etiologia , Técnicas de Sutura , Cicatrização
6.
Int J Clin Pract ; 67(7): 665-72, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23758445

RESUMO

AIMS: The present investigation was designed to test the association between carotid atherosclerosis and two simple markers of insulin resistance, i.e. HOMA-Index and TyG-Index. MATERIALS AND METHODS: The study was performed in two different cohorts. In the first cohort, 330 individuals were enrolled. Blood pressure, lipids, glucose, waist and cigarette smoking were evaluated. HOMA-IR and TyG-Index were calculated as markers of prevalent hepatic and muscular insulin resistance respectively. Carotid atherosclerosis was assessed by Doppler ultrasonography. The association between cardiovascular risk factors, markers of insulin resistance and carotid atherosclerosis was assessed by multiple logistic regression analyses. In the second cohort, limited to the evaluation of TyG-Index, 1432 subjects were studied. RESULTS: In the first cohort, TyG-Index was significantly associated with carotid atherosclerosis in a model including age, sex, diabetes, cigarette smoking and LDL cholesterol, while HOMA-IR was not. When components of metabolic syndrome were added to the model as dichotomous variables (absent/present), TyG-Index retained its predictive power. The same result was obtained when the metabolic syndrome was added to the model (absence/presence). The association between TyG-Index and carotid atherosclerosis was confirmed in the second cohort. CONCLUSIONS: The present findings suggest that TyG-Index is better associated with carotid atherosclerosis than HOMA-IR.


Assuntos
Glicemia/metabolismo , Doenças das Artérias Carótidas/diagnóstico , Resistência à Insulina/fisiologia , Triglicerídeos/metabolismo , Biomarcadores/metabolismo , Doenças Cardiovasculares/etiologia , Doenças das Artérias Carótidas/fisiopatologia , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Estudos de Coortes , Feminino , Homeostase/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Fumar/metabolismo
7.
Eur J Neurol ; 20(5): 740-7, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23121321

RESUMO

Ataxia telangiectasia (A-T) is a rare autosomal recessive disorder characterized by progressive neurological dysfunction. To date, only supportive care aimed to halt the progressive neurodegeneration is available for the treatment. Recently, an improvement of neurological signs during short-term treatment with betamethasone has been reported. To date, the molecular and biochemical mechanisms by which the steroid produces such effects have not yet been elucidated. Therefore, a review of the literature was carried out to define the potential molecular and functional targets of the steroid effects in A-T. Glucocorticoids (GCs) are capable of diffusing into the CNS by crossing the blood-brain barrier (BBB) where they exert effects on the suppression of inflammation or as antioxidant. GCs have been shown to protect post-mitotic neurons from apoptosis. Eventually, GCs may also modulate synaptic plasticity. A better understanding of the mechanisms of action of GCs in the brain is needed, because in A-T during the initial phase of cell loss the neurological impairment may be rescued by interfering in the biochemical pathways. This would open a new window of intervention in this so far incurable disease.


Assuntos
Ataxia Telangiectasia/tratamento farmacológico , Ataxia Telangiectasia/fisiopatologia , Betametasona/uso terapêutico , Proteínas de Ciclo Celular/fisiologia , Proteínas de Ligação a DNA/fisiologia , Glucocorticoides/uso terapêutico , Degeneração Neural/tratamento farmacológico , Plasticidade Neuronal/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/fisiologia , Proteínas Supressoras de Tumor/fisiologia , Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia , Betametasona/farmacologia , Proteínas de Ciclo Celular/genética , Proteínas de Ligação a DNA/genética , Glucocorticoides/fisiologia , Humanos , Modelos Genéticos , Estresse Oxidativo/fisiologia , Proteínas Serina-Treonina Quinases/genética , Proteínas Supressoras de Tumor/genética
8.
Neurogenetics ; 13(1): 97-101, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22294494

RESUMO

Investigations into migraine genetics have suggested that susceptibility loci exist on the X chromosome. These reports are supported by evidence that demonstrates male probands as having a higher proportion of affected first-degree relatives as well as the female preponderance of 3:1 that the disorder displays. We have previously implicated the Xq24-28 locus in migraine using two independent multigenerational Australian pedigrees that demonstrated excess allele sharing at the Xq24, Xq27 and Xq28 loci. Here, we expand this work to investigate a further six independent migraine pedigrees using 11 microsatellite markers spanning the Xq27­28 region. Furthermore, 11 candidate genes are investigated in an Australian case-control cohort consisting of 500 cases and 500 controls. Microsatellite analysis showed evidence of excess allele sharing to the Xq27 marker DXS8043 (LOD* 1.38 P00.005) in MF879 whilst a second independent pedigree showed excess allele sharing to DXS8061 at Xq28 (LOD* 1.5 P00.004). Furthermore, analysis of these key markers in a case control cohort showed significant association to migraine in females at the DXS8043 marker (T1 P00.009) and association with MO at DXS8061 (T1 P00.05). Further analysis of 11 key genes across these regions showed significant association of a three-marker risk haplotype in the NSDHL gene at Xq28 (P00.0082). The results of this study add further support to the presence of migraine susceptibility loci on chromosome Xq27 and Xq28 as well as point to potential candidate genes in the regions that warrant further investigation.


Assuntos
Cromossomos Humanos X/genética , Predisposição Genética para Doença , Transtornos de Enxaqueca/genética , Austrália , Estudos de Casos e Controles , Feminino , Genótipo , Haplótipos , Humanos , Masculino , Repetições de Microssatélites , Linhagem , Polimorfismo de Nucleotídeo Único
9.
J Endocrinol Invest ; 33(8): 519-25, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20061786

RESUMO

BACKGROUND: The prevalence of Paget's disease of bone (PDB) is unknown in peninsular Southern Italy, although an elevated clinical severity of the disease was reported in patients from Campania. AIM: This study was performed to evaluate the epidemiological and genetic characteristics of PDB in a rural area of Calabria, the southernmost region in the Italian peninsula. SUBJECTS AND METHODS: We examined 1068 consecutive pelvic radiographs of patients older than 40 yr referred for any reason to the "Spinelli" Hospital, Belvedere Marittimo, from January 1st 2004 to December 31st 2006. In subjects with radiological findings of pelvic PDB, a 99m Technetium methylene diphosphonate bone scan and the sequence analysis of the sequestosome 1 (SQSTM1) gene were subsequently performed. RESULTS: In the examined geographic area, the crude radiographic prevalence of pelvic PDB was 0.74% (8/1068; male:female 5:3, mean age 71.6 ± 13.1 yr) whereas the estimated overall prevalence of PDB between 0.82% and 1.21%. PDB patients from Calabria showed clinical characteristics similar to those reported in patients from Campania. The disease was also frequently complicated by osteoarthritis and the right side of the body was more affected than the left. The SQSTM1 gene analysis revealed the presence of a novel missense mutation (M401V) in exon 8 in one subject with a familial and aggressive form of PDB. CONCLUSION: The study results confirmed that patients with PDB from rural districts of Southern Italy show an earlier onset and an increased clinical severity of the disease that appears mostly independent from the presence of germinal SQSTM1 mutations.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Osteíte Deformante/epidemiologia , Osteíte Deformante/genética , Adulto , Idade de Início , Idoso , Osso e Ossos/diagnóstico por imagem , Feminino , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Mutação , Osteíte Deformante/diagnóstico por imagem , Prevalência , Radiografia , Cintilografia , Proteína Sequestossoma-1 , Medronato de Tecnécio Tc 99m
10.
J Steroid Biochem Mol Biol ; 116(1-2): 56-60, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19406238

RESUMO

Idiopathic scoliosis (IS) is a largely diffused disease in human population but its pathogenesis is still unknown. There is a relationship between scoliotic phenotype and the patient age, since in the early stage the pathology shows a ratio of 50% between male and female teenagers. During puberty the sex ratio is 8.4/1 (female/male), suggesting a sex-conditioned manifestation of the disease. Genetic inheritance of idiopathic scoliosis is still unclear although some authors claim for its X-linked dominant inheritance. There is large agreement in considering the IS as a sex-conditioned disease, in terms of steroid content and their receptor activity, although no evidence has been found yet. The blood content of 17beta-estradiol in teenagers with IS shows lower levels than teenagers of the same age without IS. Also testosterone and progesterone content are lower in IS girls with respect to the control girls. Furthermore, we extracted DNA from white blood cells of IS patients and their relatives until the third generation in order to examine estrogen receptor alpha polymorphisms, considering this tool a plausible molecular marker for IS prognosis. In this respect, we identified four polymorphisms in the exons encoding for the steroid binding domain and two other in the trans-activation domain. Our results show a clear relationship with clinical manifestation of IS.


Assuntos
Receptor alfa de Estrogênio/genética , Ligação Genética/genética , Polimorfismo Genético , Escoliose/genética , Adolescente , Estradiol/sangue , Receptor alfa de Estrogênio/metabolismo , Éxons , Feminino , Predisposição Genética para Doença , Genótipo , Humanos , Fenótipo , Progesterona/sangue , Testosterona/sangue , Adulto Jovem
11.
Neuroscience ; 155(2): 345-9, 2008 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-18632209

RESUMO

The past few years have seen rapid advances in our understanding of the genetics and molecular biology of cerebral cavernous malformations (CCM) with the identification of the CCM1, CCM2, and CCM3 genes. Recently, we have recruited a patient with an X/3 balanced translocation that exhibits CCM. By fluorescent in situ hybridization analysis, sequence analysis tools and database mining procedures, we refined the critical region to an interval of 200-kb and identified the interrupted ZPLD1 gene. We detected that the mRNA expression level of ZPLD1 gene is consistently decreased 2.5-fold versus control (P=0.0006) with allelic loss of gene expression suggesting that this protein may be part of the complex signaling pathway implicated in CCM formation.


Assuntos
Cromossomos Humanos Par 3 , Hemangioma Cavernoso do Sistema Nervoso Central/genética , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Transdução de Sinais/fisiologia , Translocação Genética , Adulto , Linhagem Celular , Quebra Cromossômica , Bases de Dados de Proteínas , Feminino , Hemangioma Cavernoso do Sistema Nervoso Central/metabolismo , Hemangioma Cavernoso do Sistema Nervoso Central/patologia , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/fisiologia , Imageamento por Ressonância Magnética , Fenótipo , Insuficiência Ovariana Primária/complicações , Insuficiência Ovariana Primária/genética , RNA Mensageiro/metabolismo , Inativação do Cromossomo X/genética
12.
Hepatogastroenterology ; 53(67): 77-81, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16506380

RESUMO

BACKGROUND/AIMS: During the past decade, the development of mini-invasive surgery has determined a resurgence in popularity of the antireflux surgery. The purpose of this study is to examine indications, preoperative evaluation, surgical techniques, and outcomes after mini-invasive surgery. METHODOLOGY: From 1996 to 2000, 25 patients with gastroesophageal reflux disease associated to hiatal hernia underwent laparoscopic surgery. The indication for surgery was failure of long-term medical therapy. All patients had severe acid reflux on 24h-pH monitoring, endoscopic evidence of esophagitis, and defective lower esophageal sphincter. Nissen fundoplication was performed in 16 patients with normal esophageal body motility, and 270 degrees posterior fundoplication in 9 patients with low esophageal motility. RESULTS: Mortality and conversion rate were 0. Mean operative time was 130 minutes and mean postoperative hospital stay 5 days. Twenty-four (96%) patients were completely cured of reflux symptoms off all medications. Transient, mild postoperative dysphagia occurred in 3 patients (12%). There was a significant improvement of the results in postoperative esophageal manometry and 24h-pH monitoring. CONCLUSIONS: Despite the fact that few patients were treated by using laparoscopic approach, results are encouraging with less morbidity and great advantages for patients. Precise selection of patients and surgical techniques are essential.


Assuntos
Refluxo Gastroesofágico/cirurgia , Laparoscopia , Adulto , Feminino , Refluxo Gastroesofágico/diagnóstico , Humanos , Laparoscopia/métodos , Masculino , Pessoa de Meia-Idade , Cuidados Pré-Operatórios , Resultado do Tratamento
13.
Minerva Med ; 96(6): 409-16, 2005 Dec.
Artigo em Italiano | MEDLINE | ID: mdl-16518303

RESUMO

Nephrolithiasis is a common multifactorial disorder affecting about 10% of the Western populations and it is characterized by the presence of small crystals and stones in the urinary tract. Uric acid nephrolithiasis (UAN) accounts for 20% of all stones but its prevalence varies between countries. Nephrolithiasis is likely caused by several factors but a genetic component has clearly been demonstrated. While studying an ancient founder population in Sardinia, we recently identified a susceptibility locus for UAN on chromosome 10. In this region we identified a missense mutation in a specific isoform of a novel gene is strongly associated with UAN. Through a comparative genomic approach, we did not found a mouse homolog even if we were able to identify the corresponding genomic region, while in Old World monkey we found a canonical gene structure with several stop codons preventing protein production. We detected expression in New World monkeys while in humans we observe a functional protein. It seems, therefore, that, to avoid human disease, a fierce selection worked to develop a renal-haematic urate homeostasis system against excessive hyperuricaemia. ZNF365 emerged during primate evolution and assumed its role in parallel with the disappearance of uricase, probably against a disadvantageous excessive hyperuricaemia.


Assuntos
Cromossomos Humanos Par 10/genética , Cálculos Renais/química , Cálculos Renais/genética , Mutação de Sentido Incorreto/genética , Ácido Úrico/metabolismo , Animais , Evolução Biológica , Cercopithecidae , Suscetibilidade a Doenças , Humanos , Camundongos
14.
Comp Biochem Physiol B Biochem Mol Biol ; 132(1): 97-105, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-11997213

RESUMO

The androgen receptor (AR) must be considered a transcription factor belonging to the steroid-thyroid hormones receptor superfamily. Previous results gained from the Harderian gland, a tubulo-alveolar gland located in the orbital cavity of the golden hamster, indicate that Harderian gland cells express mRNAs encoding for androgen, glucocorticoid, thyroid hormone (T(3)), and estrogen receptors, respectively. Since in other systems, these receptors have been related to the expression of the androgen receptor, we have studied the regulation of AR expression in primary cultures of the male hamster Harderian gland. Our in vitro experiments show that androgen, and thyroid hormones increase the expression of AR. Retinoic acids also show a positive effect on AR expression, while exposure to glucocorticoid or estrogen blocks AR expression. Since these steroids differently modulate AR expression, our results must be considered in the context of multi-hormonal control of gene expression that could act through cross-talk between members of the steroid-thyroid hormones.


Assuntos
Regulação da Expressão Gênica , Glândula de Harder/citologia , RNA Mensageiro/metabolismo , Receptores Androgênicos/biossíntese , Esteroides/metabolismo , Animais , Northern Blotting , Células Cultivadas , Cricetinae , Cicloeximida/farmacologia , Dexametasona/farmacologia , Estrogênios/metabolismo , Feminino , Glucocorticoides/metabolismo , Masculino , Mesocricetus , Inibidores da Síntese de Proteínas/farmacologia , Receptores Androgênicos/genética , Hormônios Tireóideos/farmacologia , Fatores de Tempo , Tretinoína/metabolismo , Tretinoína/farmacologia
15.
Genome Res ; 11(12): 2095-100, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11731500

RESUMO

The human pseudoautosomal region 1 (PAR1) is essential for meiotic pairing and recombination, and its deletion causes male sterility. Comparative studies of human and mouse pseudoautosomal genes are valuable in charting the evolution of this interesting region, but have been limited by the paucity of genes conserved between the two species. We have cloned a novel human PAR1 gene, DHRSXY, encoding an oxidoreductase of the short-chain dehydrogenase/reductase family, and isolated a mouse ortholog Dhrsxy. We also searched for mouse homologs of recently reported PGPL and TRAMP genes that flank it within PAR1. We recovered a highly conserved mouse ortholog of PGPL by cross-hybridization, but found no mouse homolog of TRAMP. Like Csf2ra and Il3ra, both mouse homologs are autosomal; Pgpl on chromosome 5, and Dhrsxy subtelomeric on chromosome 4. TRAMP, like the human genes within or near PAR1, is probably very divergent or absent in the mouse genome. We interpret the rapid divergence and loss of pseudoautosomal genes in terms of a model of selection for the concentration of repetitive recombinogenic sequences that predispose to high recombination and translocation.


Assuntos
Evolução Molecular , Genes/genética , NADH NADPH Oxirredutases/genética , Homologia de Sequência do Ácido Nucleico , Cromossomos Sexuais/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Mapeamento Cromossômico , Clonagem Molecular/métodos , Proteínas de Ligação ao GTP/genética , Proteínas de Ligação ao GTP/isolamento & purificação , Regulação da Expressão Gênica/genética , Humanos , Camundongos , Dados de Sequência Molecular , Cromossomos Sexuais/enzimologia
16.
Hum Mol Genet ; 10(22): 2557-67, 2001 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-11709543

RESUMO

The X-linked dominant and male-lethal disorder incontinentia pigmenti (IP) is caused by mutations in a gene called NEMO (IKK-gamma). We recently reported the structure of NEMO and demonstrated that most IP patients carry an identical deletion that arises due to misalignment between repeats. Affected male abortuses with the IP deletion had provided clues that a second, incomplete copy of NEMO was present in the genome. We have now identified clones containing this truncated copy (Delta NEMO) and incorporated them into a previously constructed physical contig in distal Xq28. Delta NEMO maps 22 kb distal to NEMO and only contains exons 3-10, confirming our proposed model. A sequence of 26 kb 3' of the NEMO coding sequence is also present in the same position relative to the Delta NEMO locus, bringing the total length of the duplication to 35.5 kb. The LAGE2 gene is also located within this duplicated region, and a similar but unique LAGE1 gene is located just distal to the duplicated loci. Mapping and sequence information indicated that the duplicated regions are in opposite orientation. Analysis of the great apes suggested that the NEMO/LAGE2 duplication occurred after divergence of the lineage leading to present day humans, chimpanzees and gorillas, approximately 10-15 million years ago. Intriguingly, despite this substantial evolutionary history, only 22 single nucleotide differences exist between the two copies over the entire 35.5 kb, making the duplications >99% identical. This high sequence identity and the inverted orientations of the two copies, along with duplications of smaller internal sections within each copy, predispose this region to various genomic alterations. We detected four rearrangements that involved NEMO, Delta NEMO or LAGE1 and LAGE2. The high sequence similarity between the two NEMO/LAGE2 copies may be due to frequent gene conversion, as we have detected evidence of sequence transfer between them. Together, these data describe an unusual and complex genomic region that is susceptible to various types of pathogenic and polymorphic rearrangements, including the recurrent lethal deletion associated with IP.


Assuntos
Antígenos de Neoplasias , Aberrações Cromossômicas , Duplicação Gênica , Incontinência Pigmentar/genética , Proteínas de Membrana , Proteínas Serina-Treonina Quinases/genética , Proteínas/genética , Animais , Antígenos de Superfície , Southern Blotting , Inversão Cromossômica , DNA/genética , DNA/isolamento & purificação , Feminino , Ordem dos Genes , Humanos , Quinase I-kappa B , Incontinência Pigmentar/patologia , Masculino , Dados de Sequência Molecular , Primatas , Deleção de Sequência , Cromossomo X/genética
18.
Am J Hum Genet ; 69(6): 1210-7, 2001 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11673821

RESUMO

Incontinentia pigmenti (IP), or "Bloch-Sulzberger syndrome," is an X-linked dominant disorder characterized by abnormalities of skin, teeth, hair, and eyes; skewed X-inactivation; and recurrent miscarriages of male fetuses. IP results from mutations in the gene for NF-kappaB essential modulator (NEMO), with deletion of exons 4-10 of NEMO accounting for >80% of new mutations. Male fetuses inheriting this mutation and other "null" mutations of NEMO usually die in utero. Less deleterious mutations can result in survival of males subjects, but with ectodermal dysplasia and immunodeficiency. Male patients with skin, dental, and ocular abnormalities typical of those seen in female patients with IP (without immunodeficiency) are rare. We investigated four male patients with clinical hallmarks of IP. All four were found to carry the deletion normally associated with male lethality in utero. Survival in one patient is explained by a 47,XXY karyotype and skewed X inactivation. Three other patients possess a normal 46,XY karyotype. We demonstrate that these patients have both wild-type and deleted copies of the NEMO gene and are therefore mosaic for the common mutation. Therefore, the repeat-mediated rearrangement leading to the common deletion does not require meiotic division. Hypomorphic alleles, a 47,XXY karyotype, and somatic mosaicism therefore represent three mechanisms for survival of males carrying a NEMO mutation.


Assuntos
Genes Letais/genética , Incontinência Pigmentar/genética , Síndrome de Klinefelter/genética , Mosaicismo/genética , Proteínas Serina-Treonina Quinases/genética , Deleção de Sequência/genética , Alelos , Criança , Pré-Escolar , Mecanismo Genético de Compensação de Dose , Feminino , Humanos , Quinase I-kappa B , Incontinência Pigmentar/patologia , Lactente , Recém-Nascido , Cariotipagem , Masculino , Meiose/genética , Linhagem , Reação em Cadeia da Polimerase , Taxa de Sobrevida
19.
Hum Mol Genet ; 10(19): 2171-9, 2001 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-11590134

RESUMO

Incontinentia pigmenti (IP) is an X-linked dominant disorder characterized by abnormal skin pigmentation, retinal detachment, anodontia, alopecia, nail dystrophy and central nervous system defects. This disorder segregates as a male lethal disorder and causes skewed X-inactivation in female patients. IP is caused by mutations in a gene called NEMO, which encodes a regulatory component of the IkappaB kinase complex required to activate the NF-kappaB pathway. Here we report the identification of 277 mutations in 357 unrelated IP patients. An identical genomic deletion within NEMO accounted for 90% of the identified mutations. The remaining mutations were small duplications, substitutions and deletions. Nearly all NEMO mutations caused frameshift and premature protein truncation, which are predicted to eliminate NEMO function and cause cell lethality. Examination of families transmitting the recurrent deletion revealed that the rearrangement occurred in the paternal germline in most cases, indicating that it arises predominantly by intrachromosomal misalignment during meiosis. Expression analysis of human and mouse NEMO/Nemo showed that the gene becomes active early during embryogenesis and is expressed ubiquitously. These data confirm the involvement of NEMO in IP and will help elucidate the mechanism underlying the manifestation of this disorder and the in vivo function of NEMO. Based on these and other recent findings, we propose a model to explain the pathogenesis of this complex disorder.


Assuntos
Proteínas de Transporte , Deleção de Genes , Incontinência Pigmentar/genética , Proteínas Quinases Ativadas por Mitógeno/genética , Mutação , Cromossomo X/fisiologia , Northern Blotting , Southern Blotting , Aberrações Cromossômicas , Estudos de Coortes , Primers do DNA/química , Éxons , Feminino , Humanos , Quinase I-kappa B , Incontinência Pigmentar/enzimologia , Masculino , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fenótipo , Reação em Cadeia da Polimerase , Polimorfismo Genético , Reação em Cadeia da Polimerase Via Transcriptase Reversa
20.
Genomics ; 76(1-3): 30-6, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11560122

RESUMO

Premature ovarian failure curtails female reproductive life and is often linked to balanced Xq/autosomal translocations in a critical region. We mapped regions around translocations at the edges of this zone (one in Xq13.3, two in Xq26) in large-insert clones and analyzed their sequence. One Xq26 region is extensively transcribed and, in agreement with a recent independent analysis, the breakpoint interrupts a gene that encodes a widely expressed peptidase. In contrast 430 kb around the second Xq26 breakpoint has no putative or detected gene content. In 260 kb around the Xq13 translocation, the breakpoint falls among a cluster of repetitive elements at least 59 kb from the only detected gene (a rarely expressed T-box family transcription factor). We discuss our results in relation to models that ascribe premature ovarian failure to interruption of ovarian genes or to a failure of interactions involving DNA of the critical region during follicle development.


Assuntos
Insuficiência Ovariana Primária/genética , Translocação Genética/genética , Cromossomo X/genética , Quebra Cromossômica/genética , Cromossomos Artificiais de Levedura/genética , Feminino , Marcadores Genéticos/genética , Humanos , Modelos Genéticos , Sitios de Sequências Rotuladas
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