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Hydrogen sulfide (H2 S) is considered to mediate plant growth and development. However, whether H2 S regulates the adaptation of mangrove plant to intertidal flooding habitats is not well understood. In this study, sodium hydrosulfide (NaHS) was used as an H2 S donor to investigate the effect of H2 S on the responses of mangrove plant Avicennia marina to waterlogging. The results showed that 24-h waterlogging increased reactive oxygen species (ROS) and cell death in roots. Excessive mitochondrial ROS accumulation is highly oxidative and leads to mitochondrial structural and functional damage. However, the application of NaHS counteracted the oxidative damage caused by waterlogging. The mitochondrial ROS production was reduced by H2 S through increasing the expressions of the alternative oxidase genes and increasing the proportion of alternative respiratory pathway in the total mitochondrial respiration. Secondly, H2 S enhanced the capacity of the antioxidant system. Meanwhile, H2 S induced Ca2+ influx and activated the expression of intracellular Ca2+ -sensing-related genes. In addition, the alleviating effect of H2 S on waterlogging can be reversed by Ca2+ chelator and Ca2+ channel blockers. In conclusion, this study provides the first evidence to explain the role of H2 S in waterlogging adaptation in mangrove plants from the mitochondrial aspect.
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Avicennia , Sulfuro de Hidrógeno , Sulfuro de Hidrógeno/farmacología , Sulfuro de Hidrógeno/metabolismo , Calcio/metabolismo , Avicennia/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Estrés OxidativoRESUMEN
ß-Thalassemia (ß-thal), a highly prevalent disease in tropical and subtropical regions of Southern China, is caused mainly by point mutations in the ß-globin gene cluster. However, large deletions have also been found to contribute to some types of ß-thal. We identified a novel 5 kb deletion in the ß-globin cluster in a Chinese patient using multiplex ligation-dependent probe amplification (MLPA), and characterized it with single molecule real-time (SMRT) sequencing, gap-polymerase chain reaction (gap-PCR) and Sanger sequencing. The deletion was located between positions 5226189 and 5231091 on chromosome 11 (GRCh38), extending from 4 kb upstream of the 5' untranslated region (5'UTR) to the second intron of the ß-globin gene. The patient with this deletion presented with microcytosis and hypochromic red cells, as well as relatively high Hb F and Hb A2 levels. Our research indicated that SMRT sequencing is a useful tool for accurate detection of large deletions. Our study broadens the spectrum of deletional ß-thalassemias and provides a perspective for further study of the function of the ß-globin cluster.
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Globinas beta , Talasemia beta , Humanos , Globinas beta/genética , Talasemia beta/diagnóstico , Talasemia beta/genética , Eliminación de Gen , Familia de Multigenes , Reacción en Cadena de la Polimerasa Multiplex , Eliminación de SecuenciaRESUMEN
Mangroves perform a crucial ecological role along the tropical and subtropical coastal intertidal zone where salinity fluctuation occurs frequently. However, the differential responses of mangrove plant at the combined transcriptome and metabolome level to variable salinity are not well documented. In this study, we used Avicennia marina (Forssk.) Vierh., a pioneer species of mangrove wetlands and one of the most salt-tolerant mangroves, to investigate the differential salt tolerance mechanisms under low and high salinity using inductively coupled plasma-mass spectrometry, transcriptomic and metabolomic analysis. The results showed that HAK8 was up-regulated and transported K+ into the roots under low salinity. However, under high salinity, AKT1 and NHX2 were strongly induced, which indicated the transport of K+ and Na+ compartmentalization to maintain ion homeostasis. In addition, A. marina tolerates low salinity by up-regulating ABA signaling pathway and accumulating more mannitol, unsaturated fatty acids, amino acids' and L-ascorbic acid in the roots. Under high salinity, A. marina undergoes a more drastic metabolic network rearrangement in the roots, such as more L-ascorbic acid and oxiglutatione were up-regulated, while carbohydrates, lipids and amino acids were down-regulated in the roots, and, finally, glycolysis and TCA cycle were promoted to provide more energy to improve salt tolerance. Our findings suggest that the major salt tolerance traits in A. marina can be attributed to complex regulatory and signaling mechanisms, and show significant differences between low and high salinity.
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Avicennia , Metaboloma , Raíces de Plantas , Salinidad , Tolerancia a la Sal , Plantas Tolerantes a la Sal , Transcriptoma , Avicennia/genética , Avicennia/fisiología , Avicennia/metabolismo , Plantas Tolerantes a la Sal/genética , Plantas Tolerantes a la Sal/metabolismo , Plantas Tolerantes a la Sal/fisiología , Raíces de Plantas/metabolismo , Raíces de Plantas/genética , Tolerancia a la Sal/genética , Regulación de la Expresión Génica de las PlantasRESUMEN
OBJECTIVE: To provide guidance for hip replacement by analyzing the variation of femoral head rotation center in different hip diseases. METHODS: A total of 5 459 patients were collected from March 2016 to June 2021, who took positive and proportional plain films of both hips for various reasons. The relative position between the rotation center of the femoral head and the apex of the greater trochanter was measured. The positive variation is more than 2 mm above the top of the great trochanter, and the negative variation is more than 2 mm below the top of the great trochanter. A total of 831 patients with variation of femoral head rotation center were collected and were divided into 4 groups according to different diseases, and the variation was counted respectively. There were 15 cases in the normal group involving 10 cases of positive variation and 5 cases of negative variation. There were 145 cases of avascular necrosis of femoral head involving 25 cases of positive variation and 120 cases of negative variation. There were 346 cases of congenital hip dysplasia involving 225 cases of positive variation(including 25 cases of typeâ , 70 cases of type â ¡, 115 cases of type â ¢ and 15 cases of type â £), and 121 cases of negative variation(including 50 cases of crowe typeâ , 60 cases of typeâ ¡, 10 cases of type â ¢ and 1 case of type â £). There were 325 cases of hip osteoarthritis group involving 45 cases of positive variation and 280 cases of negative variation. RESULTS: There was significant difference in variation of femoral head rotation center among the four groups(P<0.05). There was significant difference in variation of femoral head rotation center among different types of congenital hip dysplasia(P<0.05). There were significant differences in cervical trunk angle and eccentricity among different variations of femoral head rotation center(P<0.05). CONCLUSION: The variation of femoral head rotation center is related to cervical trunk angle and eccentricity. The variation of femoral head rotation center is an important factor in hip diseases. The variation of femoral head rotation center is different in different hip diseases. Avascular necrosis of the femoral head and osteoarthritis of the hip were mostly negative variations. With the aggravation of congenital hip dysplasia, the variation of femoral head rotation center gradually changed from negative variation to positive variation.The variation of femoral head rotation center should be paid attention to in the preoperative planning of hip arthroplasty. It is of great significance to select the appropriate prosthesis and place the prosthesis accurately.
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Artroplastia de Reemplazo de Cadera , Luxación Congénita de la Cadera , Prótesis de Cadera , Humanos , Cabeza Femoral/diagnóstico por imagen , Cabeza Femoral/cirugía , Luxación Congénita de la Cadera/cirugía , Artroplastia de Reemplazo de Cadera/métodos , Fémur/cirugía , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Cadmium (Cd) contamination is becoming a widespread environmental problem. However, the differential responsive mechanisms of Cd hyperaccumulator Solanum nigrum to low or high dose of Cd are not well documented. In this study, phenotypic and physiological analysis firstly suggested that the seedlings of S. nigrum showed slight leaf chlorosis symptoms under 25 µM Cd and severe inhibition on growth and photosynthesis under 100 µM Cd. Further proteomic analysis identified 105 differentially expressed proteins (DEPs) in the Cd-treated leaves. Under low dose of Cd stress, 47 DEPs are mainly involved in primary metabolic processes, while under high dose of Cd stress, 92 DEPs are mainly involved in photosynthesis, energy metabolism, production of phytochelatin and reactive oxygen species (ROS). Protein-protein interaction (PPI) network analysis of DEPs support above differential responses in the leaves of S. nigrum to low and high dose of Cd treatments. This work provides the differential responsive mechanisms in S. nigrum to low and high dose of Cd, and the theoretical foundation for the application of hyperaccumulating plants in the phytoremediation of Cd-contaminated soils.
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Contaminantes del Suelo , Solanum nigrum , Solanum nigrum/metabolismo , Cadmio/metabolismo , Proteómica , Contaminantes del Suelo/metabolismo , Raíces de Plantas/metabolismo , Biodegradación Ambiental , SueloRESUMEN
Lactobacillus casei Zhang is a widely recognized probiotic bacterium, which is being commercially used in China. To study the gene expression dynamics of L. casei Zhang during fermentation in soymilk, a whole genome microarray was used to screen for differentially expressed genes when grown to the lag phase, the late logarithmic phase, and the stationary phase. Comparisons of different transcripts next to each other revealed 162 and 63 significantly induced genes in the late logarithmic phase and stationary phase, of which the expression was at least threefold up-regulated and down-regulated, respectively. Approximately 38.4% of the up-regulated genes were associated with amino acid transport and metabolism notably for histidine and lysine biosynthesis, followed by genes/gene clusters involved in carbohydrate transport and metabolism, lipid transport and metabolism, and inorganic ion transport and metabolism. The analysis results suggest a complex stimulatory effect of soymilk-based ecosystem on the L. casei Zhang growth. On the other hand, it provides the very first insight into the molecular mechanism of L. casei strain for how it will adapt to the protein-rich environment.
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Fermentación , Lacticaseibacillus casei/genética , Probióticos/metabolismo , Leche de Soja , Aminoácidos/metabolismo , Animales , Carbono/metabolismo , China , Perfilación de la Expresión Génica , Regulación Bacteriana de la Expresión Génica , Transporte Iónico/genética , Lacticaseibacillus casei/crecimiento & desarrollo , Lacticaseibacillus casei/metabolismo , Metabolismo de los Lípidos/genéticaRESUMEN
In China, Tomato chlorosis virus (ToCV) and Tomato yellow leaf curl virus (TYLCV) are widely present in tomato plants. The epidemiology of these viruses is intimately associated with their vector, the whitefly (Bemisia tabaci MED). However, how a ToCV+TYLCV mixed infection affects viral acquisition by their vector remains unknown. In this study, we examined the growth parameters of tomato seedlings, including disease symptoms and the heights and weights of non-infected, singly infected and mixed infected tomato plants. Additionally, the spatio-temporal dynamics of the viruses in tomato plants, and the viral acquisition and transmission by B. tabaci MED, were determined. The results demonstrated that: (i) ToCV+TYLCV mixed infections induced tomato disease synergism, resulting in a high disease severity index and decreased stem heights and weights; (ii) as the disease progressed, TYLCV accumulated more in upper leaves of TYLCV-infected tomato plants than in lower leaves, whereas ToCV accumulated less in upper leaves of ToCV-infected tomato plants than in lower leaves; (iii) viral accumulation in ToCV+TYLCV mixed infected plants was greater than in singly infected plants; and (iv) B. tabaci MED appeared to have a greater TYLCV, but a lower ToCV, acquisition rate from mixed infected plants compared with singly infected plants. However, mixed infections did not affect transmission by whiteflies. Thus, ToCV+TYLCV mixed infections may induce synergistic disease effects in tomato plants.
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OBJECTIVE: To analyze the hematological characteristics of Chinese Gγ+(Aγδß)0-thalassemiaï¼SEA-HPFH and Taiwan type ß-thalassemia. METHODS: Hemoglobin electrophoresis and blood routine test were used to analyze the hematological indexes of all peripheral blood samplesï¼PCR-Flow fluorescent hybridization and Gap-PCR were used to detect the globin gene mutations and the data were analyzed statistically. RESULTS: The 3 types of deletion ß- Thalassemia patients were showed as hypochromic small cell anemia. The MCH and MCV values of Taiwan type ß-thalassemia patients were the lowest. The results of hemoglobin electrophoresis showed that the increasing of HbF was found in all of the 3 types. Except for the decreasing of Hb A2 in Chinese Gγ+(Aγδß)0-thalassemiaï¼the levels of Hb A2 in the other two deletion ß-thalassemia patients were significantly increased. Except for Hb, there were significant differences in MCV, MCH, Hb A2 and HbF between Chinese Gγ+(Aγδß)0-thalassemia and SEA-HPFH(P<0.001). CONCLUSION: Through analyze the hematological characteristics, it can be provide that the guidance for the differential diagnosis and genetic consultation of the three commonest deletion ß-thalassemia in Chinese.
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Talasemia , Talasemia beta , China , Diagnóstico Diferencial , Hemoglobina Fetal , Humanos , Mutación , Talasemia beta/diagnóstico , Talasemia beta/genéticaRESUMEN
OBJECTIVE: To investigate whether ß-globin gene 3'UTR+101G>C (HBB:c.*233G>C) variant has genetic effect and provide basis for gene diagnosis and genetic counseling. METHOD: Whole blood cell analysis and capillary zone electrophoresis (CZE) were used to analyze the hematological indexes. The most frequent 23 mutations in southern Chinese individuals were routinely measured by PCR-flow fluorenscence immunmicrobeads assay. Sanger sequencing was used to detect the other variants of ß-globin gene (HBB). RESULTS: In 463 cases, a total of 7 cases with HBB:c.*233G>C variant were detected, among them 4 cases carried other pathogenic variants of HBB gene (2 cases were in trans, 2 cases were in cis), who had typical hematological characteristics of mild ß-thalassemia, and 3 cases also carried abnormal hemoglobin variation, but did not have hematological characteristics of ß-thalassemia. CONCLUSION: The study shows that HBB:c.*233G > C variant has no obvious genetic effect and should be a benign polymorphism.
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Hemoglobinas Anormales , Talasemia beta , Regiones no Traducidas 3' , Hemoglobinas Anormales/genética , Humanos , Mutación , Globinas beta/genética , Talasemia beta/genéticaRESUMEN
OBJECTIVE: To analyze the hematological characteristics of Hb Broomhill and Hb Hornchurch, and prenatal diagnosis should be carried out in two families. METHODS: RBC parameters and hemoglobin electrophoretogram were analyzed on the peripheral blood of all patients, and amniotic fluid was collected for prenatal diagnosis. PCR-Flow fluorescent hybridization and Sanger sequencing were performed for gene diagnosis of thalassemia. RESULTS: Three cases of Hb Broomhill were detected, including 2 cases with common SEA α-thalassemia, which was characterized by hypochromic microcytic mild anemia, the capillary electrophoregram revealed a tiny shoulder peak before the Hb A peak; 1 case was diagnosed as Hb Hornchurch combined with ß-thalassemia, which also showed mild anemia. Hemoglobin electrophoretogram showed an abnormal hemoglobin variant peak at Hb A2 zone. CONCLUSION: The carriers of Hb Broomhill and Hb Hornchurch do not have microcytic hypochromic anemia, which do not aggravate the hematological symptoms, such as anemia when being combined with thalassemia of the same type.
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Anemia Hipocrómica , Hemoglobinas Anormales , Talasemia alfa , Talasemia beta , Hemoglobinas Anormales/genética , Heterocigoto , Humanos , Talasemia alfa/diagnóstico , Talasemia alfa/genéticaRESUMEN
OBJECTIVE: To investigate the gene diagnosis and phenotypes analysis for a couple with ß-thalassemia suspected from of blood routine test and hemoglobin electrophoresis, as well as the prenatal gene diagnosis of the fetus. METHODS: The gene mutation of ß-globin in the samples of peripheral blood of pregnant woman and her husband, as well as amniotic fluid of pregnant woman were analyzied and identified by using PCR-RDB and Sanger sequencing. RESULTS: The detection showed that the heterozygote mutation of IVS-â ¡-654 (C>T), which is common mutation of ß-globin gene, existed in pregnant woman, while her husband carried a rare mutation CD29 (c.90 C>T) of ß-globin gene. The prenatal diagnosis indicated that the fetus inherited with mutation from the parents, fetus genotype was ßIVS-â ¡-6541/ßCD29. CONCLUSION: The CD29(C>T) mutation of ß-globin gene has been identified in Chinese population first. Although this mutation type is symonymous mutation, but its carrier displays phenotype of ß-thalaessmia. Therefore, the attention to this mutation should be paid considering the genetic risk. It contributes to genetic counseling and prenatal gene diagnosis.
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Talasemia beta , Análisis Mutacional de ADN , Femenino , Heterocigoto , Humanos , Fenotipo , Embarazo , Mutación Silenciosa , Globinas betaRESUMEN
OBJECTIVE: To perform genetic analysis, prenatal diagnosis and preimplantation genetic diagnosis (PGD) in a family with a rare deletional ß- thalassemia. METHODS: Hematological parameters of the peripheral blood collected from all the family members were analyzed by whole blood cell analysis and capillary zone electrophoresis (CZE). Polymerase chain reaction-reverse dot blot (PCR-RDB) was used to identify 17 common ß- thalassemia gene mutations, the multiplex ligation-dependent probe amplification (MLPA) and gap-polymerase chain reaction (gap-PCR) were used to identify ß- globin gene cluster deletions. Chorionic villus sample or umbilical cord blood was obtained for prenatal diagnosis. Oligo-cells from blastocyst biopsy were collected for preimplantation genetic diagnosis by whole genome amplification and next generation sequencing. RESULTS: The proband was a carrier of Taiwanese deletion ß- thalassemia, two fetuses were both thalassemia majors. The PGD results showed that 6 of 11 tested embryos could be choose for transplantation. CONCLUSION: The Taiwanese deletion is a rare type deletion of ß- globin gene cluster, and it can lead to thalassemia intermedia or thalassemia major when compounded with other ß- globin gene mutation. PGD is another choice for thalassemia couples.
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Diagnóstico Preimplantación , Talasemia beta , Femenino , Pruebas Genéticas , Humanos , Embarazo , Diagnóstico Prenatal , Talasemia alfa , Talasemia beta/genéticaRESUMEN
Microindels, defined as mutations that result in a colocalized microinsertion and microdeletion with a net gain or loss of between 1 and 50 nucleotides, may be an important contributor to cancer. We report the first comprehensive analysis of somatic microindels. Our large database of mutations in the lacI transgene of Big Blue((R)) mice contains 0.5% microindels, 2.8% pure microinsertions, and 11.5% pure microdeletions. There appears to be no age, gender, or tissue-type specificity in the frequency of microindels. Of the independent somatic mutations that result in a net in-frame insertion or deletion, microindels are responsible for 13% of protein expansions and 6% of protein contractions. These in-frame microindels may play a crucial role in oncogenesis and evolution via "protein tinkering" (i.e., modest expansion or contraction of proteins). Four characteristics suggest that microindels are caused by unique mechanisms, not just simple combinations of the same mechanisms that cause pure microinsertions and pure microdeletions. First, microinsertions and microdeletions commonly occur at hotspots, but none of the 30 microindels are recurrent. Second, the sizes of the deletions and insertions in microindels are larger and more varied than in pure microdeletions and pure microinsertions. Third, microinsertions overwhelmingly repeat the adjacent base (97%) while the insertions in microindels do so only infrequently (17%). Fourth, analysis of the sequence contexts of microindels is consistent with unique mechanisms including recruitment of translesion DNA synthesis polymerases. The mouse somatic microindels have characteristics similar to those of human germline microindels, consistent with similar causative mechanisms in mouse and human, and in soma and germline.
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Eliminación de Gen , Células Germinativas/fisiología , Mutación de Línea Germinal , Mutagénesis Insercional , Factores de Edad , Animales , Proteínas Bacterianas/genética , Secuencia de Bases , Células Eucariotas/citología , Células Eucariotas/efectos de los fármacos , Células Eucariotas/fisiología , Femenino , Células Germinativas/citología , Células Germinativas/efectos de los fármacos , Humanos , Represoras Lac , Masculino , Ratones , Ratones Transgénicos , Datos de Secuencia Molecular , Mutagénesis Insercional/fisiología , Mutación , Conformación de Ácido Nucleico , Especificidad de Órganos , Proteínas Represoras/genética , Análisis de Secuencia de ADN , Caracteres SexualesRESUMEN
Microindels are unique, infrequent mutations that result in inserted and deleted sequences of different sizes (between one and 50 nucleotides) at the same nucleotide position. Little is known about the mutational mechanisms that are responsible for these mutations. From our database of 6,016 independent somatic mutational events in the lacI gene in Big Blue mice, we assembled the 30 microindels (0.5%) for analysis. Microindels with one nucleotide inserted and two nucleotides deleted (1-2 microindels) accounted for seven (23%) of the microindels observed, with the remaining microindels distributed among 21 other combinations of insertion and deletion sizes. A preferential occurrence of 1-2 microindels (20%) was also observed in human germline transmitted mutations in the Human Gene Mutation Database (HGMD). An examination of the sequence flanking the mouse 1-2 microindels did not reveal obvious site specificity or associated secondary structure. A detailed examination of 1-2 microindels did not reveal the features typical of pure microinsertion and microdeletion events, but rather suggested a unique mutational mechanism. The 1 bp insertion in 1-2 microinsertions, and pure 1 bp insertions show distinct features. The mechanism for 1-2 microindels is not obviously a simple combination of pure microinsertion and microdeletion events. The dramatic enhancement of 1-2 microindels requires explanation. We speculate that certain error-prone polymerases may be responsible for the preferential occurrence of 1-2 microindels in both somatic tissues and germ cells. It is estimated that a human adult carries roughly 400 billion somatic 1-2 microindels with the potential to predispose to cancer.
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Mutagénesis Insercional/genética , Eliminación de Secuencia/genética , Animales , Emparejamiento Base/genética , Bases de Datos Genéticas , Mutación de Línea Germinal/genética , Humanos , Ratones , Ratones Transgénicos , Neoplasias/genética , Nucleótidos/genéticaRESUMEN
To better define the time course of spontaneous mutation frequency in middle to late adulthood of the mouse, measurements were made at 10, 14, 17, 23, 25, and 30 months of age in samples of adipose tissue, liver, cerebellum (90% neurons), and the male germline (95% germ cells). A total of 46 million plaque-forming units (pfus) were screened at the six time points and 1,450 circular blue plaques were harvested and sequenced. These data improve resolution and confirm the previously observed occurrence of at least two tissue-specific profiles of spontaneous mutation frequency (elevation with age in adipose tissue and liver, and constancy with age in neurons and male germ cells), a low mutation frequency in the male germline, and a mutation pattern unchanged with age within a tissue. These findings appear to extend to very old age (30 months). Additional findings include interanimal variation in spontaneous mutation frequency is larger in adipose tissues and liver compared with neurons and male germ cells, and subtle but significant differences in the mutation pattern among tissues, consistent with a minor effect of tissue-specific metabolism. The presumptive unaltered balance of DNA damage and repair with age in the male germline has evolutionary consequences. It is of particular interest given the controversy over whether or not increasing germline mutation frequency with paternal age underlies the reports associating older males with a higher incidence of some types of genetic disease. These most detailed measurements available to date regarding the time course of spontaneous mutation frequency and pattern in individual tissues help to constrain hypotheses regarding the role of mutational mechanisms in DNA repair and aging.
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Envejecimiento/genética , Análisis Mutacional de ADN/métodos , Mutación/genética , Especificidad de Órganos/genética , Tejido Adiposo/química , Factores de Edad , Animales , Células Germinativas/química , Hepatocitos/química , Masculino , Ratones , Ratones Mutantes , Neuronas/químicaRESUMEN
OBJECTIVE: To understand the genotype of α and ß-globin, as well as the polymorphism of ß-globin gene in Cantonese in recent years, and to provide an effective genetic diagnosis for thalassemia (thal). METHODS: The single-tube complex PCR was used to detect 3 types of deletional α-thal, reverse dot blotting (RDB)/PCR to detect 3 kinds of undeletional α-thal-αCS, αQS, αWSand 18 kinds of ß-thal mutations which were common in Chinese population. A total of 454 cases from Guangdong were undergone thal genotype genetic diagnosis. Among the 454 cases, 142 cases were selected to perform the single nucleotide polymorphisms (SNPs) analysis of ß- globin gene by denaturing high-performance liquid chromatography (DHPLC)combining the whole gene sequencing. RESULTS: Of the 454 cases, 438 were diagnosed as thalassemia, including 246 of α-thal, 164 of ß-thal and 28 of αß-thal. In 246 α-thal cases, deletions were the dominant mutations, including 197 cases of αα/--(SEA), 20 of αα/-α(3.7) and 9 of αα/-α(4.2). In 164 ß- thal cases, heterozygotes accounted for 92.7% (152/164), the main genotypes were CD41- 42, IVS-II-654, ï¹£28 and CD17, and the dual heterozygotes and homozygotes accounted for 4.9% (8/164) and 2.4% (4/164), respectively. The result of ß-globin gene screening by DHPLC combining with sequencing was consistent with that of RDB. Moreover, we also found 9 kinds of SNP, in which 2 were unreported, the IVS-I-13 G> A and IVS-II- 310 T>C. In the tested samples, the frequency of 4 kinds SNP was high, among which 3 kinds SNPs-rs713040, rs10768683 and rs1609812 were carried together. CONCLUSION: The dominant genotypes were αα/--(SEA) in α-thal cases, CD41-42, IVS-II-654, -28 and CD17 in ß-thal. The frequency of ß-thal heterozygotes, homozygotes and αß-thal is high. DHPLC combining the whole ß-globin gene sequencing can effectively detect the common ß-thal mutation and even new mutations or SNPs. In Cantonese, the frequency of SNP rs713040, rs10768683, rs7480526 and rs1609812 of ß-globin gene was high, and there may exist genetic linkage between rs713040, rs10768683 and rs1609812.
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Polimorfismo de Nucleótido Simple , Talasemia alfa/genética , Globinas beta/genética , Talasemia beta/genética , Adolescente , Adulto , Anciano , Niño , Preescolar , China/epidemiología , Análisis Mutacional de ADN , Femenino , Frecuencia de los Genes , Genotipo , Heterocigoto , Homocigoto , Humanos , Lactante , Masculino , Persona de Mediana Edad , Adulto Joven , Talasemia alfa/epidemiología , Talasemia beta/epidemiologíaRESUMEN
Mutations are the substrate of cancer. Yet, little is known about the degree and nature of mutations in tumors because measurement of mutation load in tumors and normal tissues was generally not possible until the advent of transgenic mouse mutation detection systems. Herein, we present the first analysis of mutation frequency and pattern in thymic tumors from a mouse model of Li-Fraumeni syndrome (p53+/- murine model) using the Big Blue assay with sequencing of all mutants. We also make the first characterization of mutation frequency and pattern in p53-deficient extra-thymic cancers. The data more than triple the literature on all non-mismatch repair deficient tumors for which mutations are identified by sequence analysis, allowing mutation frequency and pattern to be determined. Most tumors had a normal mutation frequency and a normal mutation pattern. Five tumors showed modest increases in mutation frequency (2.3-fold or less). Alterations in mutation patterns were uncommon, tumor-specific and not necessarily associated with increases in mutation frequency. Given the data from two spontaneous tumors (normal mutation frequency with an abnormal pattern in a p53-/- mouse and low mutation frequency in a p53+/+ control mouse), we hypothesize that tumors sometimes can carry a low mutation load. The study was not without certain caveats: mutation load could not be compared between tumor and normal tissue from the same animal; sample sizes for extra-thymic tumor types were small, and only point mutations and deletions, insertions and indels up to 2 kb were detected. However, the data clearly show key differences in tumors from p53+/- mice compared with mismatch repair deficient tumors; a lack of dramatic increase in mutation frequency and absence of a signature of mutation.