RESUMO
DNA methylation with 5-methylcytosine (5mC) has been reported in the genome of several eukaryotes, with marked differences between vertebrates and invertebrates. DNA methylation is poorly understood as its role in evolution in insects. Drosophila gouveai (cluster Drosophila buzzatii) presents larvae that develop obligatorily in necrotic tissues of cacti in nature, with the distribution of populations in South America, and plasticity of phenotypes in insect-plant interaction. We characterize organisms at developmental stages and analyze variations at multiple methylation-sensitive loci in pupae, and adult flies using methylation sensitive amplification polymorphism. We obtained 326 loci with CCGG targets in the genome of D. gouveai. Genomic regions with molecular lengths from 100 to 700 pb were most informative about methylation states. Multiple loci show differences in methylation-sensitive sites (MSL) concerning developmental stages, such as in pupae (MSL = 40), female reproductive tissue (MSL = 76), and male reproductive tissues (MSL = 58). Our results are the first evidence of genome-wide methylation in D. gouveai organisms.
Assuntos
Cactaceae , Drosophila , Animais , Drosophila/genética , Cactaceae/genética , Sequência de Bases , Genômica , Metilação , Metilação de DNARESUMO
PURPOSE: This study aimed to evaluate the epigenetic reprogramming of ICR1 (KvDMR1) and ICR2 (H19DMR) and expression of genes controlled by them as well as those involved in methylation, demethylation, and pluripotency. METHODS: We collected germinal vesicle (GV) and metaphase II (MII) oocytes, and preimplantation embryos at five stages [zygote, 4-8 cells, 8-16 cells, morula, and expanded blastocysts (ExB)]. DNA methylation was assessed by BiSeq, and the gene expression was evaluated using qPCR. RESULTS: H19DMR showed an increased DNA methylation from GV to MII oocytes (68.04% and 98.05%, respectively), decreasing in zygotes (85.83%) until morula (61.65%), and ExB (63.63%). H19 and IGF2 showed increased expression in zygotes, which decreased in further stages. KvDMR1 was hypermethylated in both GV (71.82%) and MII (69.43%) and in zygotes (73.70%) up to morula (77.84%), with a loss of methylation at the ExB (36.64%). The zygote had higher expression of most genes, except for CDKN1C and PHLDA2, which were highly expressed in MII and GV oocytes, respectively. DNMTs showed increased expression in oocytes, followed by a reduction in the earliest stages of embryo development. TET1 was downregulated until 4-8-cell and upregulated in 8-16-cell embryos. TET2 and TET3 showed higher expression in oocytes, and a downregulation in MII oocytes and 4-8-cell embryo. CONCLUSION: We highlighted the heterogeneity in the DNA methylation of H19DMR and KvDMR1 and a dynamic expression pattern of genes controlled by them. The expression of DNMTs and TETs genes was also dynamic owing to epigenetic reprogramming.
Assuntos
Blastocisto , Oócitos , Humanos , Animais , Bovinos , Oócitos/metabolismo , Blastocisto/metabolismo , Metilação de DNA/genética , Zigoto/fisiologia , Desenvolvimento Embrionário/genética , Oxigenases de Função Mista/genética , Oxigenases de Função Mista/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismoRESUMO
Recent studies have shown that maternal vitamin D deficiency (VDD) causes long-term metabolic changes in offspring. However, little is known about the impact of maternal VDD on offspring endocrine pancreas development and insulin secretion in the adult life of male and female animals. Female rats (Wistar Hannover) were fed either control (1000 IU Vitamin D3/kg), VDD (0 IU Vitamin D3/kg), or a Ca2+-enriched VDD diet (0 IU Vitamin D3/kg + Ca2+ and P/kg) for 6 weeks and during gestation and lactation. At weaning, VDD status was confirmed based on low serum calcidiol levels in dams and pups. Next, male and female offspring were randomly separated and fed a standard diet for up to 90 days. At this age, serum calcidiol levels were restored to normal levels in all groups, but serum insulin levels were decreased in VDD males without affecting glucagon levels, glycemia, or glucose tolerance. Islets isolated from VDD males showed lower insulin secretion in response to different glucose concentrations, but this effect was not observed in VDD females. Furthermore, VDD males, but not females, showed a smaller total pancreatic islet area and lower ß cell mass, an effect that was accompanied by reduced gene expression of Ins1, Ins2, Pdx1, and SLC2A2. The decrease in Pdx1 expression was not related to the methylation profile of the promoter region of this gene. Most of these effects were observed in the male VDD+Ca2+ group, indicating that the effects were not due to alterations in Ca2+ metabolism. These data show that maternal VDD selectively impairs the morphology and function of ß cells in adult male offspring rats and that female offspring are fully protected from these deleterious effects.
Assuntos
Células Secretoras de Insulina , Insulina , Ratos Wistar , Deficiência de Vitamina D , Animais , Feminino , Células Secretoras de Insulina/metabolismo , Masculino , Deficiência de Vitamina D/metabolismo , Ratos , Gravidez , Insulina/sangue , Insulina/metabolismo , Efeitos Tardios da Exposição Pré-Natal/metabolismo , Efeitos Tardios da Exposição Pré-Natal/etiologia , Fatores Sexuais , Secreção de InsulinaRESUMO
Spondylometaphyseal dysplasia with cone-rod dystrophy is a rare autosomal-recessive disorder characterized by severe short stature, progressive lower-limb bowing, flattened vertebral bodies, metaphyseal involvement, and visual impairment caused by cone-rod dystrophy. Whole-exome sequencing of four individuals affected by this disorder from two Brazilian families identified two previously unreported homozygous mutations in PCYT1A. This gene encodes the alpha isoform of the phosphate cytidylyltransferase 1 choline enzyme, which is responsible for converting phosphocholine into cytidine diphosphate-choline, a key intermediate step in the phosphatidylcholine biosynthesis pathway. A different enzymatic defect in this pathway has been previously associated with a muscular dystrophy with mitochondrial structural abnormalities that does not have cartilage and/or bone or retinal involvement. Thus, the deregulation of the phosphatidylcholine pathway may play a role in multiple genetic diseases in humans, and further studies are necessary to uncover its precise pathogenic mechanisms and the entirety of its phenotypic spectrum.
Assuntos
Colina-Fosfato Citidililtransferase/genética , Osteocondrodisplasias/genética , Retinose Pigmentar/genética , Adolescente , Brasil , Criança , Pré-Escolar , Colina-Fosfato Citidililtransferase/metabolismo , Feminino , Genes Recessivos , Homozigoto , Humanos , Lactente , Masculino , Oftalmologia/métodos , LinhagemRESUMO
Trisomy 16q is a clinically recognizable entity presenting with a wide spectrum of abnormalities. Only five infants with a diagnosis of partial trisomy 16q13 â qter have been previously reported, and all died during the first year of life. We report the clinical and molecular cytogenetic findings in a patient with trisomy 16q13 â qter due to the presence of a supernumerary marker chromosome (SMC). The child presented with microcephaly, ambiguous genitalia, cardiac malformations and dysmorphic features. Cytogenetic investigation using GTG-banding, spectral karyotyping (SKY) and fluorescence in situ hybridization analyses revealed an SMC of maternal origin with karyotype der(15)t(15;16)(q13;q13). Specific genotype-phenotype correlations among different segments of the 16q region cannot yet be defined. We suggest that the involvement of the entire region spanning from 16q11 to 16q22 is necessary for the characteristic phenotype of the trisomy 16q.
Assuntos
Anormalidades Múltiplas/genética , Trissomia/genética , Cromossomos Humanos Par 16/genética , Transtornos do Desenvolvimento Sexual/genética , Cardiopatias Congênitas/genética , Humanos , Lactente , Cariótipo , Masculino , Microcefalia/genética , FenótipoRESUMO
Background: Cancer is a group of heterogeneous diseases characterized by several disruptions of the genetic and epigenetic components of cell biology. Some types of cancer have been shown to be constituted by a mosaic of cells with variable differentiation states, with more aggressive tumors being more undifferentiated. In most cases, undifferentiated tumor cells express associated embryonic markers such as the OCT4, NANOG, SOX2, and CARM1 genes. The ectopic or reminiscent expression of some master regulator genes of pluripotency has been indicated as the cause of the poorly differentiated state of tumors, and based on the evidence of some reports, can be used as a possible therapeutic target. Considering this information, a more detailed investigation of the expression of pluripotency-associated genes is necessary to evaluate the roles of these genes in the etiology of some tumors and their use targets of therapy. Methods: The expression of four pluripotency-related genes was investigated (OCT4, NANOG, SOX2, and CARM1) in the most malignant primary human brain tumor, glioblastoma (GBM). Results and Conclusion: The results demonstrated a signature of OCT4/SOX2/CARM1 genes and a significant increase of CARM1 expression in GBM cases.
RESUMO
Vascular endothelial growth factor (VEGF) is relevant for normal pregnancy, and abnormalities in VEGF functions are associated with hypertensive disorders of pregnancy. Because there are few studies on how VEGF genetic polymorphisms affect susceptibility to pre-eclampsia (PE), and no studies on how they affect susceptibility to gestational hypertension (GH), we compared VEGF genotype and haplotype distributions in normotensive and hypertensive pregnancies. Genotypes and haplotypes for VEGF polymorphisms (C-2578A, G-1154A and G-634C) were determined in 303 pregnant women (108 healthy pregnant, HP; 101 with GH and 94 with PE). When white and non-white pregnant women were considered together, no significant differences were found in the distributions of VEGF genotypes or haplotypes (P > 0.05) in the three groups. However, with only white subjects, significant differences were found in genotypes distributions for two (C-2578A and G-634C) VEGF polymorphisms (both P < 0.05) between the HP and the PE groups. Importantly, the haplotype including the variants C-2578, G-1154 and C-634, which is associated with higher VEGF gene expression, was less common in the PE group compared with the HP group (4% versus 16%; P = 0.0047). However, we found no significant differences in VEGF haplotypes distributions when the HP and GH groups were compared (P > 0.05). These findings suggest a protective effect for the 'C-2578, G-1154 and C-634' haplotype against the development of PE, but no major effects of VEGF gene variants on susceptibility to GH.
Assuntos
Predisposição Genética para Doença , Hipertensão Induzida pela Gravidez/genética , Pré-Eclâmpsia/genética , Fator A de Crescimento do Endotélio Vascular/genética , Adulto , Feminino , Genótipo , Haplótipos , Humanos , Gravidez , Adulto JovemRESUMO
BACKGROUND: The aim of the present study was to evaluate the methylation pattern in the suppressor of cytokine signaling 1 (SOCS1) gene in smokers and non-smokers with chronic periodontitis (CP). METHODS: Methylation-specific polymerase chain reaction (PCR) was performed to determine the methylation status of the SOCS1 promoter in 45 saliva samples from smokers and non-smokers with CP. RESULTS: Cells from the saliva of CP patients who smoked were 7.08 times more likely to have a methylated SOCS1 promoter than cells from the saliva of non-smoking patients. CONCLUSIONS: SOCS1 gene promoter methylation, with its potential effects on the expression of this gene, seems to be a consequence of exposure to tobacco and not to periodontal disease. Further studies are needed to elucidate the relationship between the epigenetic control of immune response gene expression, exposure to environmental factors, and the development, progression, and prognosis of CP.
Assuntos
Periodontite Crônica , Metilação de DNA , Células Epiteliais , Humanos , Regiões Promotoras Genéticas , Saliva , Proteína 1 Supressora da Sinalização de CitocinaRESUMO
OBJECTIVE: To analyze whether telomere length, X-chromosome inactivation (XCI), and androgen receptor (AR) GAG polymorphism are related to idiopathic premature ovarian insufficiency (POI). DESIGN: Case-control study. SETTING: University hospital. PATIENT(S): A total of 121 women, including 46 nonsyndromic POI and 75 controls. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Age, weight, height, body mass index (BMI), systolic and diastolic arterial pressure, E2, androstenedione, T, and C-reactive protein were assessed. Telomere length was estimated by quantitative real-time polymerase chain reaction, XCI was measured using the Human Androgen Receptor and X-linked retinitis pigmentosa 2 (RP2) methylation assays. AR and FMR1 polymorphism was assessed by quantitative fluorescent polymerase chain reaction and sequencing. RESULT(S): Premature ovarian insufficiency women had a higher mean age, weighed less, and exhibited lower C-reactive protein, E2, and androstenedione levels. The AR polymorphism did not differ between the groups. Four patients had premutation (55-200 CGG repeats), and none displayed a full mutation in the FMR1 gene. However, patients with POI showed shorter telomere length and higher frequency of skewed XCI. Extreme skewing (≥90%) was observed in 15% of women with POI, and shorter telomeres correlated with XCI skewing in both groups. CONCLUSION(S): Skewed XCI and shortened telomere length were associated with idiopathic POI, despite no alterations in the AR and FMR1 genes. Additionally, there is a tendency for women with short telomeres to exhibit skewed XCI.
Assuntos
Insuficiência Ovariana Primária/diagnóstico , Insuficiência Ovariana Primária/genética , Encurtamento do Telômero/genética , Telômero/genética , Inativação do Cromossomo X/genética , Adolescente , Adulto , Estudos de Casos e Controles , Feminino , Proteína do X Frágil da Deficiência Intelectual/genética , Humanos , Estudos Prospectivos , Receptores Androgênicos/genética , Adulto JovemRESUMO
Rearrangements involving chromosomes 2 and 22 were described not only as acquired abnormalities in a variety of human neoplasias but also in the constitutional karyotype suggesting the existence of a greater fragility in some specific regions in these chromosomes. Patients with DiGeorge and Velocardiofacial syndromes have a deletion on 22q11 leading to haploinsufficiency for one or more gene(s). We report a patient with velocardiofacial syndrome in which cytogenetic and fluorescence in situ hybridization analysis showed a rare t(2;22) and deletion in the 22q11 region.
Assuntos
Cromossomos Humanos Par 22/genética , Cromossomos Humanos Par 2/genética , Síndrome de DiGeorge/genética , Translocação Genética/genética , Pré-Escolar , Humanos , Cariotipagem , MasculinoRESUMO
Patients with 1q duplication have demonstrated a wide range of multiple congenital abnormalities. Alterations involving this chromosomal region have being described in hematopoietic malignancies and a series of candidate genes that may be associated with neoplasias have been mapped in this region. We describe a case of partial trisomy 1q "syndrome" and acute monocytic leukemia. Cytogenetic study of the bone marrow cells by GTG-banding and spectral karyotyping (SKY) showed dup(1)(q23q44) in all cells analyzed. The dismorphological features with the dup(1q) suggest a constitutional chromosome alteration and the first, in our knowledge, association of a trisomy 1q "syndrome" with AML.
Assuntos
Anormalidades Múltiplas/genética , Cromossomos Humanos Par 1 , Leucemia Monocítica Aguda/genética , Trissomia , Anormalidades Múltiplas/patologia , Medula Óssea/patologia , Bandeamento Cromossômico/métodos , Feminino , Humanos , Lactente , Leucemia Monocítica Aguda/patologia , Cariotipagem EspectralRESUMO
CONTEXT: There is great interindividual variability in the response to recombinant human (rh) GH therapy in patients with Turner syndrome (TS). Ascertaining genetic factors can improve the accuracy of growth response predictions. OBJECTIVE: The objective of the study was to assess the individual and combined influence of GHR-exon 3 and -202 A/C IGFBP3 polymorphisms on the short- and long-term outcomes of rhGH therapy in patients with TS. DESIGN AND PATIENTS: GHR-exon 3 and -202 A/C IGFBP3 genotyping (rs2854744) was correlated with height data of 112 patients with TS who remained prepubertal during the first year of rhGH therapy and 65 patients who reached adult height after 5 ± 2.5 yr of rhGH treatment. MAIN OUTCOME MEASURES: First-year growth velocity and adult height were measured. RESULTS: Patients carrying at least one GHR-d3 or -202 A-IGFBP3 allele presented higher mean first-year growth velocity and achieved taller adult heights than those homozygous for GHR-fl or -202 C-IGFBP3 alleles, respectively. The combined analysis of GHR-exon 3 and -202 A/C IGFBP3 genotypes showed a clear nonadditive epistatic influence on adult height of patients with TS treated with rhGH (GHR-exon 3 alone, R² = 0.27; -202 A/C IGFBP3, R² = 0.24; the combined genotypes, R² = 0.37 at multiple linear regression). Together with clinical factors, these genotypes accounted for 61% of the variability in adult height of patients with TS after rhGH therapy. CONCLUSION: Homozygosity for the GHR-exon3 full-length allele and/or the -202C-IGFBP3 allele are associated with less favorable short- and long-term growth outcomes after rhGH treatment in patients with TS.
Assuntos
Deleção de Genes , Hormônio do Crescimento Humano/uso terapêutico , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Polimorfismo de Nucleotídeo Único , Receptores da Somatotropina/genética , Síndrome de Turner/tratamento farmacológico , Síndrome de Turner/genética , Adulto , Alelos , Estatura/efeitos dos fármacos , Brasil , Resistência a Medicamentos , Éxons , Feminino , Estudos de Associação Genética , Homozigoto , Terapia de Reposição Hormonal , Hormônio do Crescimento Humano/genética , Humanos , Regiões Promotoras Genéticas , Proteínas Recombinantes/uso terapêutico , Resultado do TratamentoRESUMO
We adapted a method that allows the identification of X chromosome copy number by quantitative real-time polymerase chain reaction (PCR) in a short amount of time. It may be used for sex and aneuploidy involving X chromosome large population screening tests.
Assuntos
Aneuploidia , Cromossomos Humanos X , Testes Genéticos/métodos , Reação em Cadeia da Polimerase/métodos , Estudos de Casos e Controles , Duplicação Cromossômica , Cromossomos Humanos X/genética , Feminino , Dosagem de Genes , Genética Populacional/métodos , Humanos , Masculino , Aberrações dos Cromossomos Sexuais , Transtornos dos Cromossomos Sexuais/diagnóstico , Transtornos dos Cromossomos Sexuais/genéticaRESUMO
OBJECTIVE: Studies carried out to assess the effects of antiretroviral drugs (ARV) in HIV-1 infected pregnant women have demonstrated carbohydrate intolerance. Some reports also refer to the effect of disturbances in the expression of the insulin-like growth factor (IGF) system on pancreas beta-cell function in humans and IGF-2/ApaI polymorphisms have been associated with obesity and features of the metabolic syndromes. In the present study, we tested the association between IGF-2/ApaI genotype and hyperglycemia in HIV-1 infected pregnant women receiving ARV. DESIGN: We studied IGF-2/ApaI polymorphism in 87 healthy pregnant women, 43 HIV-1 infected pregnant women taking ARV with hyperglycemia during pregnancy, and 43 HIV-1-negative pregnant women with gestational diabetes. Blood samples were obtained for DNA extraction, PCR and genotyping. Data were analyzed statistically by the Kolmogorov-Smirnov normality, ANOVA and chi-square tests. RESULTS: There were no significant differences in genotype frequency among the three groups analyzed. Considering the HIV-1-infected pregnant women, there were no significant differences in genotype frequency between the zidovudine group and the triple antiretroviral treatment group. There were no significant differences in allele frequencies among the groups evaluated. Non-white pregnant women tended to present the GG genotypes compared to white pregnant women. CONCLUSION: These results contribute to a better understanding of metabolic glycemic disorders in HIV-1-infected pregnant women using ARV, showing that IGF-2/ApaI polymorphisms are not responsible as a single causative factor of glycemic alterations. These data indicate that other variables should be studied in order to explain these glycemic abnormalities.
Assuntos
Fármacos Anti-HIV/uso terapêutico , Desoxirribonucleases de Sítio Específico do Tipo II/genética , Infecções por HIV/sangue , Infecções por HIV/tratamento farmacológico , Infecções por HIV/genética , HIV-1/metabolismo , Fator de Crescimento Insulin-Like II/genética , Polimorfismo Genético , Área Sob a Curva , Estudos de Casos e Controles , Feminino , Genótipo , Homozigoto , Humanos , Gravidez , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/genética , Fatores de TempoRESUMO
AIMS: Polymorphisms in the endothelial nitric oxide synthase (eNOS) gene have been inconsistently associated with preeclampsia. We compared genotype and haplotype frequencies of three eNOS gene polymorphisms in normotensive and hypertensive pregnancies. METHODS: Genotypes and haplotypes for eNOS polymorphisms (T-786C, Glu298Asp and intron 4 b/a) were determined in 326 pregnant women (110 healthy pregnancies, 103 gestational hypertensives and 113 preeclamptic). RESULTS: No differences were observed in the frequencies of genotypes and alleles of the three polymorphisms among the groups (all p > 0.05). However, the haplotype 'T Glu a' was more common in healthy pregnancies than in gestational hypertensives or preeclamptic (20 vs 6 and 6%, respectively; p < 0.0032). Conversely, the haplotype 'C Glu a' was more common in gestational hypertensives and preeclamptic than in healthy pregnancies (17 vs 17 and 5%; p = 0.0061). CONCLUSION: These findings suggest a contribution of eNOS haplotypes to the development of hypertensive disorders of pregnancy that is obscured when specific eNOS genotypes alone are considered.
Assuntos
Haplótipos , Hipertensão Induzida pela Gravidez/genética , Óxido Nítrico Sintase Tipo III/genética , Polimorfismo Genético , Pré-Eclâmpsia/genética , Adulto , Alelos , Análise de Variância , Estudos de Casos e Controles , Feminino , Frequência do Gene , Predisposição Genética para Doença , Genótipo , Humanos , Gravidez , Adulto JovemRESUMO
Velocardiofacial syndrome (VCFS) is a relatively common developmental disorder characterized by craniofacial anomalies and conotruncal heart defects. Many VCFS patients present hemizygous deletions on part of chromosome 22q11.2; suggestive that haploinsufficiency in this region is responsible for this etiology. Most 22q11.2 deletions occur sporadically, although in some cases the deletion may be transmitted. A total of 29 VCFS patients and their parents were genotyped using six consecutive polymorphic markers (STS) of the chromosome 22q11.2: D22S420, D22S941, D22S264, D22S306, D22S425, and D22S257. The results revealed that 72% (21/29) of the patients harbored a deletion involving the polymorphic markers D22S420, D22S941, and/or D22S264. Haplotype analysis showed that among the patients studied, the deletions were either of maternal or paternal origin. Our findings demonstrated that independently of their size, any deletion occurring in the VCFS critical region is enough to confer the patient phenotype.
Assuntos
Deleção Cromossômica , Cromossomos Humanos Par 22/genética , Síndrome de DiGeorge/genética , Anormalidades Múltiplas , Adolescente , Criança , Anormalidades Craniofaciais/genética , DNA/análise , Feminino , Marcadores Genéticos , Genótipo , Humanos , Masculino , Linhagem , Fenótipo , Reação em Cadeia da PolimeraseAssuntos
Aracnodactilia , Coloboma , Contratura , Pálpebras/anormalidades , Doenças da Íris , Humanos , Lactente , Recém-Nascido , Masculino , Fenótipo , SíndromeRESUMO
The CCCTC - binding factor (CTCF) is a protein involved in repression, activation, hormone-inducible gene silencing, functional reading of imprinted genes and X-chromosome inactivation. We analyzed CTCF gene expression in bovine peripheral blood, oocytes and in different cellular stages (2-4 cells, 8-16 cells, 16-32 cells, morulae, and blastocysts) of in vitro fertilized embryos. This is the first report of CTCF expression in oocytes and preimplantation bovine embryos and has implications for the production of embryonic stem cells and the development of novel medical technologies for humans.