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Objective:To investigate the arousal mechanism after sevoflurane anesthesia using orexinergic modulation in dorsal raphe nucleus(DRN) by optogenetic and chemogenetic techniques in rats.Methods:Forty-five healthy male Hcrt-Cre rats, aged 10-12 weeks, weighing 220-250 g, were divided into 6 groups by the random number table method: optical-excitatory group (CHR2 group, n=5), optical-inhibitory group (eNpHR group, n=5), optical-control group (O-CON group, n=5); chemogenetic-excitatory group (hm3Dq group, n=10), chemogenetic-inhibitory group (hm4Di group, n=10) and chemogenetic-control group (C-CON group, n=10). The optogenetic or chemogenetic techniques were used in each group. Three weeks after injecting the rat virus, anesthesia was induced and maintained with 2.7% sevoflurane anesthesia in 1.5 L/min O 2, and the EEG data were continuously recorded throughout the process. The burst suppression ratio (%BSR) was recorded at 2 min before and of laser stimulation. Combining optogenetic and chemogenetic strategies, it was investigated that whether activation of orexinergic projection to DRN could modulate anesthetic behaviors during sevoflurane anesthesia. Results:Compared with C-CON group, the recovery of righting reflex (RORR) time was significantly shortened after sevoflurane anesthesia in hm3Dq group ( P<0.05), and the RORR time was significantly prolonged after sevoflurane anesthesia in hm4Di group and eNpHR group ( P<0.05). Compared with O-CON group or the baseline at 2 min before light stimulation, the %BSR was significantly decreased during 473nm laser stimulation in CHR2 group ( P<0.05), and no statistically significant change was found in the %BSR during 473nm laser stimulation in eNpHR group ( P>0.05). Compared with O-CON group, the RORR time was significantly shortened after sevoflurane anesthesia in CHR2 group ( P<0.05). Conclusions:Lateral hypothalamic area orexin-DRN neural circuit plays a key role in promoting arousal from general anesthesia in rats.
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Objective:Charcot-Marie-Tooth disease (CMT) comprises a group of clinically and genetically heterogeneous inherited neuropathies with an estimated prevalence of 1 in 2500. This study aimed to analyze the clinical and mutational characteristics of Chinese CMT patients with MFN2, BSCL2 and LRSAM1 variants.Methods:In this study, genetic analysis was performed in 206 Chinese patients at Chinese PLA General Hospital from December 2012 to March 2020 with clinical diagnosis of CMT, and reported variants of MFN2, BSCL2 and LRSAM1 related to CMT2.Results:We reported ten MFN2 mutations in ten unrelated patients (7 male, 3 female), two of whom had positive family history. Three novel mutations were detected including c.475-2A>G (splicing); c.687dupA (p.E230Rfs*16) and c.558dupT (p.S186fs). We reported three BSCL2 mutations of four unrelated patients, including c.461C>G (p.S154W), c.461C>T(p.S154L), and novel variants of c.1309G>C (p.A437P) and c.845C>T (p.A282V). Furthermore, two novel variants of LRSAM1, including c.1930G>T (p.G644C) and c.1178T>A (p.L393Q) were detected in two unrelated patients.Conclusion:Mutational spectrum of MFN2-, BSCL2-and LRSAM1-related CMT disease is expanded with the identification of novel variants in Chinese patients.
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With the development and popularity of genetic testing, more and more clinicians are over-relying on genetic testing for the diagnosis of hereditary myopathy, a rare disease, leading to misdiagnosis for patients and causing a huge economic burden to the society and family. It is essential for clinicians to further understand the limitations of gene testing and attach more attention to the clinical characteristics, which might be suggestive for the clinical diagnosis of hereditary myopathy. During the process of accurate diagnosis, gene testing should be selected based on the clinical manifestations, promoting its rational application in the diagnosis of hereditary myopathy.
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La ineficacia de las estrategias actuales para el control químico de los mosquitos vectores plantea la necesidad de desarrollar enfoques novedosos, entre estos están las estrategias genéticas para reducir las poblaciones de mosquitos vectores o sustituirlos por aquellos que no son capaces de transmitir patógenos, esto se logra a través de herramientas moleculares que permiten la manipulación y transgénesis de genes. Las secuencias del genoma de los mosquitos y las bases de datos de marcadores de secuencias expresadas asociadas permiten investigaciones a gran escala para proporcionar nuevos conocimientos sobre las vías evolutivas, bioquímicas, genéticas, metabólicas y fisiológicas. Además, la genómica comparativa revela las bases de los mecanismos evolutivos con especial atención a las interacciones específicas entre vectores y patógenos. Se ha desarrollado tecnología de transgénesis para el mosquito de la fiebre amarilla y dengue, Aedes aegypti. Se ha logrado integración exitosa de ADN exógeno en la línea germinal de este mosquito con los elementos transponibles. La disponibilidad de múltiples elementos y genes marcadores proporciona un poderoso conjunto de herramientas para investigar las propiedades biológicas básicas de este insecto vector, así como los materiales para desarrollar nuevas estrategias de control genético de poblaciones de mosquitos basadas en la técnica del insecto estéril. Una de estas estrategias consiste en liberar a la población machos esterilizados por radiación; otro, de integrar un gen letal dominante bajo el control de un promotor específico en hembras inmaduras. El uso de esta técnica de modificación genética constituirá una herramienta importante para el manejo integrado de vectores(AU)
The ineffectiveness of current strategies for the chemical control of vector mosquitoes raises the need to develop novel approaches, among these are genetic strategies to reduce populations of vector mosquitoes or replace them with those that are not capable of transmitting pathogens, this is achieved through molecular tools that allow the manipulation and transgenesis of genes. Mosquito genome sequences and associated expressed sequence marker databases enable large-scale investigations to provide new insights into evolutionary, biochemical, genetic, metabolic, and physiological pathways. Furthermore, comparative genomics reveals the basis of evolutionary mechanisms with special attention to the specific interactions between vectors and pathogens. Transgenesis technology has been developed for the yellow fever and dengue mosquito, Aedes aegypti. Successful integration of exogenous DNA into the germ line of this mosquito with the transposable elements has been achieved. The availability of multiple elements and marker genes provides a powerful set of tools to investigate the basic biological properties of this insect vector, as well as the materials to develop new strategies for genetic control of mosquito populations based on the sterile insect technique. One of this strategy is to release radiation-sterilized males into the population; another, to integrate a dominant lethal gene under the control of a specific promoter in immature females. The use of this genetic modification technique will constitute an important tool for the integrated management of vectors(AU)
Subject(s)
Animals , Arboviruses , Genetic Engineering , Gene Transfer Techniques , Aedes , Arbovirus Infections , Health Strategies , Mosquito Vectors , GeneticsABSTRACT
ABSTRACT Objective: To report two patients with very-early-onset inflammatory bowel disease (VEOIBD) secondary to interleukin-10 receptor (IL-10R) mutations, explore immunophenotyping data and plasma cytokine profile on these cases compared to healthy controls, and describe the phenotype of IL-10/IL-10R mutations based on a literature review. Case description: We report on two female infants referred to our tertiary center at the age of ten months, with severe colonic and perianal disease, as well as significant malnutrition, who had shown limited response to usual inflammatory bowel disease (IBD) therapy agents. In the first case, whole-exome sequencing (WES) revealed a homozygous (c.537G>A/p.T179T) mutation in exon 4 of the IL-10RA gene, while in the second patient, compound heterozygosity was identified, also in the IL-10RA gene (chr11:117.859.199 variant A>G/p.Tyr57Cys and chr11: 117.860.335 variant G>T/p.Val123Leu). Both patients underwent hematopoietic cell transplantation (HCT). Immunological work-up of these patients revealed increased IL-10 plasma levels and increased IgA. Comments: Our case reports disclose novel findings on plasma cytokine profile in IL-10R deficiency, and we describe the severe phenotype of IL-10/IL-10R deficiency that should be recognized by physicians.
RESUMO Objetivo: Relatar os casos de duas pacientes com doença inflamatória intestinal de início muito precoce (em inglês VEOIBD) secundária a mutações do receptor de interleucina 10 (IL-10R), explorar dados de imunofenotipagem e perfil de citocinas plasmáticas nesses casos em comparação com indivíduos saudáveis e descrever o fenótipo de mutações IL-10/IL-10R com base em uma revisão da literatura. Descrição do caso: Duas lactentes do sexo feminino foram encaminhadas ao nosso centro terciário, ambas com dez meses no momento do encaminhamento, com doença colônica e perianal grave, bem como desnutrição significativa, tendo uma resposta limitada aos agentes de terapia usuais de doença inflamatória intestinal (DII). No primeiro caso, o sequenciamento completo do exoma revelou mutação homozigótica (c. 537G>A/p.T179T) no exon 4 do gene IL-10RA, enquanto no segundo caso heterozigosidade composta foi identificada também no gene IL-10RA [chr11: 117.859.199 - variante A>G/p.Tyr57Cys e chr11: 117.860.335 - variante G>T/ p.Val123Leu]. Ambas as pacientes foram submetidas a Transplante de Células-Tronco Hematopoiéticas. A investigação imunológica das pacientes revelou aumento dos níveis plasmáticos de IL-10 e aumento da IgA. Comentários: Nossos relatos de casos descrevem novos achados no perfil de citocinas plasmáticas na deficiência de IL-10R, e relatamos o fenótipo grave da deficiência de IL-10/IL-10R que deve ser reconhecido pelos médicos.
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Introducción: el objetivo de la secuenciación es determinar la composición de los nucleótidos presentes en el ADN o el ARN. Desde la finalización del proyecto genoma humano, surgieron diversas tecnologías de secuenciación rápida como Roche 454, SOLiD, Illumina, Ion Torrent, PacBio y Oxford Nanopore, más precisas y costoeficientes, que permiten desarrollar proyectos a gran escala y estudiar genes y genomas, la composición de microbiomas, enfermedades metabólicas y enfermedades genéticas que afectan a la población. Objetivo: describir los fundamentos de los métodos de secuenciación de ADN y sus aplicaciones en las ciencias biomédicas. Métodos: revisión descriptiva de las principales estrategias de secuenciación de ADN de primera, segunda y tercera generación y su aplicación en el entorno biomédico, a partir de la búsqueda de artículos en bases de datos electró-nicas especializadas en investigación científica. Se encontraron 118 documentos, de los cuales se excluyeron 6, por no cumplir con los criterios de inclusión, y se seleccionaron 112, por cumplir con todos los requisitos. Conclusiones:el surgimiento de los métodos de secuenciación de siguiente generación arroja una gran canti-dad de datos, incluidos genomas secuenciados completamente de varias especies, con un rendimiento extenso, tiempos reducidos y costoeficiencia, que lleva a la completa transformación de las ciencias de la vida y logra un progreso sin precedentes en el análisis de genomas, la evaluación de la ecología microbiana y el diagnóstico de enfermedades.
Introduction: The purpose of sequencing is to determine the composition of the nucleotides present in DNA or RNA. Since the completion of the human genome project, several sequencing technologies such as Roche 454, SOLiD, Illumina, Ion Torrent, PacBio and Oxford Nanopore have emerged as tools for rapid sequencing, with greater precision and cost-efficiency, allowing the development of lar-ge-scale projects and the study of genes and genomes, along with the composition of microbiomes and the study of metabolic and genetic diseases that affect the population. Objective: To describe the foundations of the methods of DNA sequencing and their applications in the biomedical sciences. Methods: Descriptive review of the main strategies of first, second and third generation DNA sequencing and their application in the biomedical environment. This review was carried out by searching articles in electronic databases specialized in scientific research. A total of 118 papers were found, of which 6 were excluded as they did not meet the inclusion criteria and 112 were selected as meeting all the requirements. Conclusions: The emergence of next-generation sequencing methods yielding a wealth of data, including fully sequenced genomes of various species, with extensive throughput, reduced time and cost-effec-tiveness that has led to the complete transformation of the life sciences, achieving unprecedented progress in genome analysis, assessment of microbial ecology and disease diagnosis
Introdução: o objetivo do sequenciamento é determinar a composição dos nucleotídeos presentes no DNA ou RNA. Desde a conclusão do projeto do genoma humano, surgiram diversas tecnologias de sequenciamento rápida como Roche 454, SOLiD, Illumina, Ion Torrent, PacBio e Oxford Nanopore, mais precisas e econômicas, que permitem o desenvolvimento de projetos de grande escala e estudo de genes e genomas, composição de microbiomas, doenças metabólicas e genéticas que afetam a popula-ção. Objetivo: descrever os fundamentos dos métodos de sequenciamento de DNA e suas aplicações nas ciências biomédicas. Métodos: revisão descritiva das principais estratégias de sequenciamento de DNA de primeira, segunda e terceira geração e sua aplicação no ambiente biomédico, a partir da busca de artigos em bases de dados eletrônicas especializadas em pesquisa científica. Foram encontrados 118 documen-tos, dos quais 6 foram excluídos por não atenderem aos critérios de inclusão e 112 fo-ram seleciona-dos por atenderem a todos os requerimentos. Conclusões: o surgimento de métodos de sequenciamento de próxima geração rende uma riqueza de dados, incluindo genomas totalmente se-quenciados de várias espécies, com produção extensa, tempos reduzidos e eficiência de custo, levando à transformação completa das ciências da vida e alcançando um progresso sem precedentes no genoma análise, avaliação de ecologia microbiana e diagnóstico de doenças.
Subject(s)
High-Throughput Nucleotide Sequencing , DNA , Genome, Human , Genetic Techniques , Sequence AnalysisABSTRACT
For the past three decades, a large number of genetic studies have been performed to examine genetic variants associated with asthma and its subtypes in hopes of gaining better understanding of the mechanisms underlying disease pathology and to identify genetic biomarkers predictive of disease outcomes. Various methods have been used to achieve these objectives, including linkage analysis, candidate gene polymorphism analysis, and genome-wide association studies (GWAS); however, the degree to which genetic variants contribute to asthma pathogenesis has proven to be much less significant than originally expected. Subsequent application of GWAS to well-defined phenotypes, such as occupational asthma and non-steroidal anti-inflammatory drugexacerbated respiratory diseases, has overcome some of these limitations, although with only partial success. Recently, a combinatorial analysis of single nucleotide polymorphisms (SNPs) identified by GWAS has been used to develop sets of genetic markers able to more accurately stratify asthma subtypes. In this review, we discuss the implications of the identified SNPs in diagnosis of asthma and its subtypes and the progress being made in combinatorial analysis of genetic variants.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal , Aspirin , Asthma , Asthma, Occupational , Biomarkers , Diagnosis , Genetic Association Studies , Genetic Markers , Genetic Techniques , Genome-Wide Association Study , Hope , Pathology , Phenotype , Polymorphism, Single NucleotideABSTRACT
El carcinoma de tiroides es un tumor infrecuente; constituye menos del 1% de las neoplasias malignas en la población general y el 0,5%-3% en la edad pediátrica. Existen cuatro tipos: papilar (80%-90% de los casos), folicular (5%-10%), medular (5%) y anaplásico (2%-3%). En el tipo medular, el 80% son esporádicos, y un 20% se asocia a un síndrome hereditario que se divide, fundamentalmente, en tres grupos: neoplasia endócrina múltiple 1, neoplasia endócrina múltiple 2 y carcinoma medular de tiroides familiar. Las formas hereditarias se producen por una mutación en el protooncogén RET, localizado en el brazo largo del cromosoma 10. Se presenta un caso de carcinoma medular de tiroides detectado a raíz de un estudio genético familiar con el propósito de resaltar la importancia del diagnóstico precoz y la intervención de equipos multidisciplinares expertos en esta patología para su manejo y seguimiento.
Thyroid cancer is an uncommon type of cancer, accounting less than 1% of all cancers in adults, and 0.5-3% of all cancers in children. There are four different types: papillary carcinoma (80-90% of cases), follicular (5-10%), medullary (5%) and anaplastic cell (2-3%). Eighty per cent of cases of medullary thyroid cancer are sporadic, but 20% are associated with an inherited syndrome that is divided into three groups: multiple endocrine neoplasia type 1, multiple endocrine neoplasia type 2 and familial medullary thyroid carcinoma. The inherited forms are caused by a disruption in the RET oncogene, which is located in the long arm of chromosome 10. A hereditary case of medullary thyroid carcinoma is presented. It was detected because of a familial genetic study. The purpose of the paper is emphasize the importance of the early diagnosis and the intervention of multidisciplinary teams of experts.
Subject(s)
Humans , Female , Child, Preschool , Thyroid Neoplasms/genetics , Carcinoma, Neuroendocrine/genetics , Pedigree , Thyroid Neoplasms/diagnosis , Thyroid Neoplasms/therapy , Carcinoma, Neuroendocrine/diagnosis , Carcinoma, Neuroendocrine/therapyABSTRACT
Optogenetics is a novel technique which combines optics with genetics.Using genetic means,a selected opsin protein is ectopically expressed in target neurons,which are then stimulated by light to moderate the neuronal circuit,as a consequence to regulate the animal's behaviors.Retinal degeneration like retinitis pigmentosa and aged macular degeneration causes visual impairment and eventual blindness.Optogenetics techniques have opened the door to creating artificial photoreceptors in the remaining retinal circuits of retinal degeneration retinas via gene therapy.However,there are still limitations in optogenetics technique,for example,potential risk in virus infection,the choice of target cells and the low visual resolution of the experiment animal.It has been reported that vision was successfully restored to a certain extent in animal model using optogenetics technique.With higher photosensitivity of opsin protein,longer activation kinetics and higher transfection efficiency of virus vector,optogenetics techniques' application in ophthalmology will be improved.
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Genetic factors are important causes of male infertility and account for about 30%infertility cases.Therefore, it is necessary to carry out molecular and genetic detections in the diagnosis and treatment of male infertility.Here the most commonly used techniques for molecular and genetic diagnosis of male infertility in recent years are discussed , including chromosomal abnormities analysis , Y chromosome microdeletions detection , gene mutation screening and sperm quality and function examination.
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Maternally Inherited Diabetes and Deafness (MIDD) is caused by mutations in mitochondrial DNA (mtDNA), mainly m.3243A>G. Severity, onset and clinical phenotype of MIDD patients are partially determined by the proportion ofmutant mitochondrial DNA copies in each cell and tissue (heteroplasmy). The identification ofMIDD allows a corred treatment with insulin avoiding drugs that may interfere with mitochondrial electrón chain transpon. We estimated the degree of heteroplasmy ofthe mutation m.3243A>G from blood, saliva, hair root and a muscle biopsy using quantitative PCR (qPCR) in a femóle adult patient. For this purpose, PCR producís were inserted in a vector creatingplasmids with 3243A or G. Mutant and wild-type vectors were mixed in different proportions to créate a calibration curve used to interpólate heteroplasmy percentages with qPCR threshold cycles. The proportions of m.3243A>G heteroplasmy were 62% (muscle), 14% (saliva), 6% (blood leukocytes) and 3% in hair root. Quantitative analysis of heteroplasmy showed marked variations in different tissues (highest in muscle and lowest in blood). Given the relatively high heteroplasmy found in saliva, this type of biológical sample may represent an adequate non-invasive way for assessing the presence of m.3243A>G mutations in epidemiologic studies.
Subject(s)
Female , Humans , Middle Aged , DNA, Mitochondrial/genetics , Deafness/genetics , /genetics , Mutation/genetics , Deafness/diagnosis , Deafness/pathology , /diagnosis , /pathology , Phenotype , Polymerase Chain Reaction/methodsABSTRACT
The knowledge of the human genome has led to an explosion of available genetic tests for clinical use. The methodologies used in these tests vary widely, allowing the study from chromosomes to the analysis of a single nucleotide. Prior to its use in the clinical setting, these tests should have an evaluation that includes analytical and clinical validation and determination of the clinical utility, as any other tests, including requirements for quality assurance. Recently, the CDC (Centers for Disease Control and Prevention, USA) published a guideline for Good Laboratory Practices for Molecular Genetic Testing for Heritable Diseases and Conditions, covering the pre-analytical, analytical and post-analytical phases of the tests. The document covers the importance of proper selection of tests, the availability of information on the performance of the techniques used, the quality control practices, the training of personnel involved and the report of results, to allow the adequate interpretation, including sensitivity and specificity. Considering that recent advances in genetics have changed and will continue to affect clinical practice, genetic tests must meet quality and safety requirements to enable optimal use of them.
El conocimiento del genoma humano ha dado lugar a un aumento explosivo de los test genéticos disponibles para uso clínico. Las metodologías utilizadas en este tipo de tests son muy variadas, permitiendo desde el estudio de los cromosomas hasta el análisis de una base nucleotídica. Previo a su utilización en el ámbito clínico, estos tests deben tener una evaluación que incluya su validación analítica y clínica y determinación de la utilidad clínica, además de cumplir, como cualquier otro examen, con requisitos para el aseguramiento de la calidad. Recientemente, el CDC (Centersfor Disease Control and Prevention, EE. UU) hapublicado recomendaciones para las buenas prácticas de laboratorio de tests moleculares que se utilizan para el diagnóstico de enfermedades genéticas, que abarcan la fase pre- analítica, analítica y post-analítica. Dentro de éstas destacan: la importancia de la selección adecuada de los tests, la disponibilidad de la información sobre el desempeño de las técnicas utilizadas, las prácticas de control de calidad, la capacitación del personal involucrado y la elaboración de un informe de resultados que permita al clínico interpretarlos adecuadamente, incluyendo sensibilidad y especificidad. Tomando en cuenta que los recientes avances en genética han modificado y seguirán modificando la práctica clínica, los test genéticos deben cumplir con las exigencias de calidady seguridad que permitan su uso óptimo.
Subject(s)
Humans , Genetic Testing/methods , Genetic Testing/standards , Practice Guidelines as TopicABSTRACT
Formas químicas de controle de mosquitos vetores são ineficazes, levando ao desenvolvimento de novas estratégias. Assim, foi realizada revisão das estratégias de controle genético de populações de mosquitos vetores baseada na técnica do inseto estéril. Uma delas consiste na liberação de machos esterilizados por radiação, a outra, na integração de um gene letal dominante associado a um promotor específico de fêmeas imaturas. Entre as vantagens sobre outras técnicas biológicas e químicas de controle de vetores estão: alta especificidade, não prejudicial ao meio ambiente, baixo custo de produção e alta eficácia. O uso desta técnica de modificação genética pode vir a ser uma importante ferramenta do manejo integrado de vetores.
The ineffectiveness of current strategies for chemical control of mosquito vectors raises the need for developing novel approaches. Thus, we carried out a literature review of strategies for genetic control of mosquito populations based on the sterile insect technique. One of these strategies consists of releasing radiation-sterilized males into the population; another, of integrating a dominant lethal gene under the control of a specific promoter into immature females. Advantages of these approaches over other biological and chemical control strategies include: highly species-specific, environmentally safety, low production cost, and high efficacy. The use of this genetic modification technique will constitute an important tool for integrated vector management.
Subject(s)
Animals , Male , Female , Animals, Genetically Modified , Culicidae/genetics , Insect Vectors/genetics , Mosquito Control/methods , Sensitivity and SpecificityABSTRACT
Objective To develop a reverse genetics system for Hantaan virus (HTNV) 84FLi strain by using RNA polymerase [ (pol Ⅰ)-mediated transcription. Methods Complementary DNA (cDNA) containing the coding sequence for chloramphenicol acetyhransferase (CAT) was inserted into the 5'-and 3'-terminal untranslated regions of HTNV 84FLi L segment. These chimeric cDNAs (pol Ⅰ expression cassette) were cloned into plasmids and between the human pol Ⅰ promoter and terminator to generate sense and anti-sense RNA pol Ⅰ transcription reporter plasmids. The reporter plasmids were transfeeted into 293T cells or the 1:1 combination of 293T and HTNV infected Vero cells. These cells were cotransfected with expression plasmids encoding Ⅰ. (RNA dependent RNA polymerase) and N (nucleoprotein) viral proteins, Cells were harvested 48 h post-transfection and the CAT activity was detected. The 293T cells were infected with the supernatant to explore the passage ability of CAT activity. ResultsThe reporter plasmids pLvRNA-CAT and pLcRNA-CAT were constructed successfully. CAT activity was detected in transfected cells and could also be serially passaged in the rescued virus minigenomes. Conclusion The RNA polymerase ]-driven reverse genetics system successfully rescues HTNV 84FLi minigenomes.
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Objective To analyze and compare the accuracy and utility of determining sperm DNA integrity by sperm chromatin dispersion (SCD) test and acridine orange staining (AO) test.Methods The level of DNA fragmentation was determined by SCD test and AO test in 32 adult healthy fertile men and 27 idiopathic oligozoospermia (IO) patients.Sperm nuclei with large DNA dispersion halos or with mediumsized halos were normal and nuclei with small-sized halos or no halo were abnormal.The normal sperm DNA was double strands and stained by AO as green.The damaged sperm DNA was single strand,which were stained as green for native DNA and red for denatured DNA.Results The percentage of sperm nuclei with large halos,medium-sized halos,small-sized halos and no halo evaluated bv SCD test in IO patients were (49.9±13.8)%,(11.5±5.4)%,(11.9±6.1)%and(26.7±10.0)%,and they were(73.2±6.2)%,(14.7±6.3)%,(6.8±2.9)%and(5.3±2.2)%in healthy control group,respectively.There was significant difference between two groups(t=8.576,P<0.01;t=2.083,P<0.05;t=4.284,P<0.01;t=11.823,P<0.01).The percentage of sperm DNA fragmentation was (38.6±12.1)%in IO patients and was (12.1±5.2)% in fertile men,respectively.A statistically significant difference was found between IO patients and healthy control group under SCD test (t=11.995,P<0.01).AO test showed no significant differences between IO patients and healthy control group (t=1.626,P>0.05).The percentage of sperm DNA fragmentation evaluated by AO test in IO patients was (45.5 ±13.8)%,and it was (39.8±13.3)%in healthy control group.Conclusions Sperm DNA fragmentation may lead to male infertility.The SCD is effective in testing the sperm DNA fragmentation as a screening procedure to determine semen quality during basic infertility investigation for clinical use.