RESUMO
Cytogenetic analysis remains a powerful and cost-effective technology, and has wide applicability in genetic counseling for infertile males. Chromosomal rearrangements are thought to be one of the major genetic factors that influence male infertility. Some carriers with balanced reciprocal translocation have been identified as having oligozoospermia or azoospermia, and there is an association between balanced translocation and recurrent abortion. Researchers have reported the involvement of chromosome 4 translocations in male factor infertility and recurrent miscarriages. A translocation breakpoint might interrupt the structure of an important gene, and it is associated with reproductive failure. However, the clinical characteristics of the breakpoints in chromosome 4 translocations have not been studied. Here, we report the breakpoints in chromosome 4 translocation and the clinical features presented in carriers to enable informed genetic counseling of these patients. Of 82 patients with balanced reciprocal translocations, 14 were carriers of the chromosome 4 translocation: four presented with pregestational infertility (clinical manifestations: oligozoospermia, severe oligozoospermia, or azoospermia), whereas 10 presented with gestational infertility (able to conceive but with a tendency to miscarry). The breakpoint at 4q12 was associated with pregestational infertility, whereas the breakpoints at 4q13, 4q21, 4q25, and 4q32 were associated with gestational infertility. However, the breakpoint at 4q35 was associated with both pregestational and gestational infertility. Chromosome 4 translocation carriers with pregestational or gestational infertility should be counseled on chromosomal breakpoints and the different technologies available to assist reproduction.
Assuntos
Aborto Espontâneo/genética , Azoospermia/genética , Pontos de Quebra do Cromossomo , Cromossomos Humanos Par 4/genética , Oligospermia/genética , Feminino , Aconselhamento Genético , Heterozigoto , Humanos , Masculino , Gravidez , Translocação GenéticaRESUMO
Balanced reciprocal translocations are associated with reproductive failure. Some reciprocal translocation carriers exhibit azoospermia or oligozoospermia, and an association exists between these chromosomal abnormalities and recurrent abortion. Previous reports have indicated the involvement of chromosome 7 translocations in male infertility and recurrent miscarriage. A translocation breakpoint can occur within an important gene, interrupting its structure and leading to male infertility. However, clinical characteristics resulting from chromosome 7 translocation breakpoints have not been studied. Here, we report such breakpoints and their associated clinical features, to enable informed genetic counseling of carriers. Balanced reciprocal translocations were found in 1.57% of the tested patients. Among these 82 individuals, 14 (17.07%) carried a chromosome 7 translocation, of which, five presented with pregestational infertility and clinical manifestations of oligozoospermia or necrospermia, while nine presented with gestational infertility (i.e., were able to conceive, but often resulting in miscarriage). Breakpoints at 7q31 and 7q36 were associated with pregestational infertility, whereas those at 7p10, 7q21.2, 7q22, and 7q32 were connected to gestational infertility. However, the breakpoint at 7p15 was associated with both. Chromosome 7 translocation carriers with pregestational or gestational infertility should be counseled on chromosomal breakpoints and the various molecular technologies available for assisted reproduction.
Assuntos
Quebra Cromossômica , Cromossomos Humanos Par 7/genética , Aconselhamento Genético , Translocação Genética , Heterozigoto , Humanos , Cariotipagem , MasculinoRESUMO
Reciprocal translocation is closely associated with male infertility and recurrent miscarriages. Balanced reciprocal translocations associated with reproductive failures are predominantly observed on chromosome 1. Additionally, infertile male patients present a number of breakpoints throughout chromosome 1. A translocation breakpoint might interrupt the structure of an important gene, leading to male infertility. Here, we report the breakpoints on chromosome 1 translocation and the clinical features presented in carriers, to enable informed genetic counseling of these patients. Balanced reciprocal translocations were found in 1.57% of the tested patients. Among 82 patients, 23 patients (28.05%) were carriers of the chromosome 1 translocation: 12 presented pre-gestational infertility with clinical manifestations of azoospermia or oligozoospermia, while 11 patients presented gestational infertility (able to conceive but with a tendency to miscarry or give birth to a stillborn). The breakpoint at 1p22 was predominantly observed in these patients; additionally, breakpoints at 1p31.2, 1p10, and 1q25 were associated with gestational infertility. Breakpoints at 1p13, 1q12, and 1q21 were associated with pre-gestational infertility. These results suggested that breakpoints at 1p32, 1p13, and 1q21 were predominantly associated with pre-gestational infertility, while that at 1q25 was associated with gestational infertility. Chromosome 1 translocation carriers with infertility presenting as azoospermia or oligospermia should be counseled on chromosomal breakpoints and the different molecular technologies available to facilitate reproduction.
Assuntos
Cromossomos Humanos Par 1/genética , Aconselhamento Genético , Translocação Genética , Quebra Cromossômica , Heterozigoto , Humanos , Infertilidade Masculina/genética , Cariótipo , MasculinoRESUMO
This study aimed to determine the influence of vector structure on dual Bt gene expression and establish an efficient expression vector using Cry1Ac and Cry3A genes. Four vectors (N4, N5, N10, and S23) were developed and used for genetic transformation of tobacco to obtain insect-resistant transgenic lines. The vectors were constructed using the MAR structure, applying different promoter and enhancer sequences, and changing the transgene open-reading frame sequence. The average Cry1Ac toxalbumin expression quantity was 67 times higher in N5 than in N4 transgenic lines (8.77 and 0.13 µg/g, respectively). In contrast, the average Cry3A toxalbumin expression quantity was 1.5 times higher in N4 than in N5 lines (12.70 and 8.21 µg/g, respectively). The sequences of both Bt genes significantly influenced toxalbumin expression, although upstream Bt genes presented lower expression levels. The average Cry1Ac toxalbumin content was 13 times higher in the transgenic lines of AtADH 5'-non-translated sequence N5 (8.77 mg/g) than in the omega N10 lines (0.67 mg/g). Furthermore, the average Cry1Ac toxalbumin content was 5 times higher in MAR N5 than in non-MAR S23 lines (8.77 and 1.63 mg/g, respectively). The average Cry3A toxalbumin content was 1.3 times higher in N5 than in S23 lines (8.21 and 6.48 mg/g, respectively). Moreover, toxalbumin expression levels differed significantly among the S23-transformed lines. The MAR structure applied on both ends of the genes increased both the level and stability of exogenous gene expression. In conclusion, N5 was the most optimal of the four tested vectors.
Assuntos
Proteínas de Bactérias/genética , Endotoxinas/genética , Proteínas Hemolisinas/genética , Lepidópteros/fisiologia , Nicotiana/genética , Folhas de Planta/genética , Agrobacterium tumefaciens/genética , Animais , Bacillus thuringiensis/genética , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/biossíntese , Endotoxinas/biossíntese , Expressão Gênica , Vetores Genéticos , Proteínas Hemolisinas/biossíntese , Herbivoria , Larva/fisiologia , Controle Biológico de Vetores , Folhas de Planta/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Nicotiana/metabolismo , Transformação Genética , TransgenesRESUMO
The aims of this study were to demonstrate the clinical and cytogenetic results of amniocentesis (AS) cases in Northeast China, to compare the incidence of different kinds of chromosomal abnormalities, and to study the association between the detection rate of chromosomal abnormalities and different indications for prenatal diagnosis. Cytogenetic analysis was performed on long-term tissue cultures of 2500 second-trimester amniotic fluid samples. The most common indication for genetic AS was abnormal maternal serum-screening test (69.56%), followed by advanced maternal age (15.04%). Chromosomal abnormality was detected in 206 (8.24%) of the 2500 samples. The detection rate of abnormal karyotypes was 62.5% in the group in which one member of the couple was a carrier of a chromosome abnormality; in the group having a positive result from noninvasive prenatal testing, the frequency was 50%. To determine the origin of fetal chromosome abnormal karyotype, 45 fetuses were analyzed. Of these, 20 were found to be de novo abnormalities and 25 were familial. The frequency and proportion of abnormal karyotypes varied substantially across different maternal AS indications. Knowing the origin and type of chromosomal abnormality would help determine termination or continuation of the pregnancy.
Assuntos
Amniocentese , Transtornos Cromossômicos/diagnóstico , Transtornos Cromossômicos/genética , Citogenética , Diagnóstico Pré-Natal , Cariótipo Anormal , Adulto , Amniocentese/métodos , China/epidemiologia , Aberrações Cromossômicas , Transtornos Cromossômicos/epidemiologia , Citogenética/métodos , Feminino , Humanos , Incidência , Masculino , Gravidez , Resultado da Gravidez , Segundo Trimestre da Gravidez , Diagnóstico Pré-Natal/métodos , Estudos RetrospectivosRESUMO
The aim of this study was to evaluate the correlation between chromosomal polymorphisms and male infertility. The patients were diagnosed with azoospermia or oligospermiaby a semen analysis. Chromosomal analysis was performed on peripheral blood lymphocytes obtained from the patients, with standard G-banding and C-banding. Y chromosome microdeletions were detected by multiplex polymerase chain reaction (PCR) amplification. The parents of 35 polymorphic probands were also subjected to chromosomal analysis, and their detailed reproductive histories were surveyed. The frequency of autosomal polymorphisms did not differ significantly among the infertile patients and fertile control individuals. The frequency of the Yqh-variant increased with the decrease in sperm count; this appeared at a significantly higher frequency in the azoospermia group (57.2 vs 24.3 vs 0%). The results of PCR amplification indicated that 32.14% of the patients with Yqh ± had microdeletions in the Y chromosome. The parents of the probands with the same chromosomal polymorphisms as the probands (among the 35 recalled families) did not show any adverse reproductive history. We observed no significant correlations between autosomal polymorphisms and male infertility. However, we observed a significant increase in the frequency of Yqh- in the azoospermic patients. This may be attributed to Y chromosome microdeletions, although the association between Y chromosome microdeletions and Y chromosome variants remains to be elucidated.
Assuntos
Povo Asiático/genética , Infertilidade Masculina/genética , Polimorfismo Genético , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/genética , Azoospermia/genética , Estudos de Casos e Controles , China , Bandeamento Cromossômico , Deleção Cromossômica , Cromossomos Humanos Y/genética , Feminino , Humanos , Infertilidade Masculina/diagnóstico , Infertilidade Masculina/epidemiologia , Cariótipo , Masculino , Oligospermia/genética , Linhagem , Reação em Cadeia da Polimerase , Prevalência , Aberrações dos Cromossomos Sexuais , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/diagnóstico , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/epidemiologia , Contagem de EspermatozoidesRESUMO
We report that a 30-year-old woman with mental retardation was referred for prenatal diagnoses during pregnancy. An ultrasound scan showed that the heart structure and function of the fetus were normal. Cytogenetic analysis showed that the female karyotype was 47,XX, t(17; 22) (q21; q11), +21. The woman's husband had a normal male karyotype and was phenotypically normal. During this first pregnancy, an amniocentesis, which was done at 19 weeks, revealed that the fetal karyotype was 46,XX, t(17; 22) (q21; q11). Fluorescence in situ hybridization testing of amniotic fluid gave a normal result for chromosome 21. The child was a phenotypically normal female baby.
Assuntos
Cromossomos Humanos Par 17/genética , Cromossomos Humanos Par 22/genética , Síndrome de Down/genética , Padrões de Herança/genética , Mães , Núcleo Familiar , Translocação Genética , Adulto , Líquido Amniótico/citologia , Bandeamento Cromossômico , Feminino , Humanos , Cariotipagem , FenótipoRESUMO
A reciprocal translocation between the short arm of chromosome 1 and the long arm of chromosome 3 was observed in a pedigree of three carriers (proband, and his brother and mother). In this study, the three carriers had different clinical manifestations: the proband with infertility, his brother with spousal miscarriages, and his mother with no adverse reproductive history. Cytogenetic analysis of metaphase chromosomes was performed, and triple-color fluorescence in situ hybridization was applied to the detection of aneuploidy sperm related to the interchromosomal effect (ICE). An increase of aneuploidy of chromosome 21 in the proband and aneuploidy of chromosomes 13, 21, and Y in the brother were observed. Since patients with reciprocal translocations and spermatogenetic impairment are candidates, with their partners, for intracytoplasmic sperm injection, the study of the level of sperm aneuploidy rates would provide useful information for couples at risk, as well as contributing to a better understanding of the ICE.
Assuntos
Aneuploidia , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 3 , Infertilidade Masculina/genética , Espermatozoides/metabolismo , Translocação Genética , Adulto , Cromossomos Humanos Par 13 , Cromossomos Humanos Par 21 , Cromossomos Humanos Y , Análise Citogenética , Feminino , Aconselhamento Genético , Heterozigoto , Humanos , Hibridização in Situ Fluorescente , Masculino , Pessoa de Meia-Idade , Linhagem , Espermatozoides/patologiaRESUMO
Y chromosome microdeletions can cause male infertility and are classified as natural transmission and de novo mutations. To examine the source of these deletions in Chinese men and to provide a theoretical and laboratory basis for genetic counseling, patients from Northeast China with primary male infertility (N = 22) and their fathers were investigated. Karyotype analysis was performed on peripheral blood lymphocytes using standard G-banding. Multiplex polymerase chain reaction amplification using 18 specific sequence-tagged sites was selected to detect Y chromosome microdeletions. De novo mutations were observed in 17 father-son pairs, leading to a mutation rate of 77.27% (17/22), while the vertical transmission of Yq AZFc microdeletions was detected in 5 cases of the families investigated (29.41%, 5/17). There were no statistically significant differences between vertically transmitted and de novo mutations in men with AZFc deletions regarding age, testicular volume, and reproductive hormone levels. Most Y chromosome microdeletions in men from Northeast China are the result of de novo mutations via natural conception, and men with Yq AZFc deletions showed no clear differences between vertical transmission and de novo mutations.
Assuntos
Povo Asiático/genética , Infertilidade Masculina/genética , Transtornos do Cromossomo Sexual no Desenvolvimento Sexual/genética , China , Bandeamento Cromossômico , Deleção Cromossômica , Cromossomos Humanos Y/genética , Deleção de Genes , Humanos , Cariótipo , Cariotipagem , Masculino , Linhagem , Análise de Sequência de DNA , Sitios de Sequências Rotuladas , Aberrações dos Cromossomos SexuaisRESUMO
Balanced chromosomal translocations in men can cause failure of spermatogenesis owing to meiotic impairment. Male carriers may exhibit normozoospermia, although clinical manifestations can include oligozoospermia or azoospermia, oligozoospermia or normozoospermia. Here, we reported the characteristics of balanced reciprocal translocations in men from northeastern China, and explored the relationship between sperm count and reproductive performance, to enable informed genetic counseling. The frequency of balanced reciprocal translocations was found to be 1.62%. Semen analysis showed that 5.9% of male carriers had azoospermia, 43.1% had oligozoospermia, and 51.0% had normozoospermia. Of the 25 men with a balanced reciprocal translocation and azoospermia or oligozoospermia, chromosome 1 was the most commonly often involved in the translocation. However, in the 26 normozoospermic men with a balanced reciprocal translocation and normozoospermia, chromosome 3 was most commonly implicated. Fifty percent of men with a balanced reciprocal translocation conceived a pregnancy that went to term. Our data suggest that of all chromosomes, chromosomes 1 and 3 are the most commonly involved chromosomes in balanced reciprocal such translocations in northeastern Chinese men. Karyotype analysis should be performed for men with azoospermia, oligozoospermia, and those in couples having suffered recurrent miscarriages. Natural conception should be discussed during genetic counseling for male carriers of balanced chromosomal translocations with normozoospermia.
Assuntos
Azoospermia/genética , Aconselhamento Genético , Heterozigoto , Oligospermia/genética , Reprodução/genética , Translocação Genética , Adulto , Azoospermia/diagnóstico , Azoospermia/patologia , China , Segregação de Cromossomos , Cromossomos Humanos Par 1 , Cromossomos Humanos Par 3 , Feminino , Aptidão Genética , Humanos , Cariotipagem , Masculino , Oligospermia/diagnóstico , Oligospermia/patologia , Gravidez , Análise do Sêmen , Contagem de Espermatozoides , Espermatogênese/genética , Espermatozoides/metabolismo , Espermatozoides/patologiaRESUMO
In this study, the genetic diversity among ten populations of the Bombay duck was studied on the basis of sequence-related amplified polymorphism (SRAP). The ten populations were collected from the East China Sea and South China Sea areas. A total of 98 loci were obtained from 292 individuals using eight SRAP primers. The average proportion of polymorphic loci, genetic diversity (H), and Shannon's information index were 75.20%, 0.2478, and 0.3735, respectively. Nei's genetic distance and Shannon's information index between the ten populations ranged from 0.0410 to 0.3841 and from 0.2396 to 0.4506, and the averages Nei's gene diversity index (H = 0.2478) and Shannon's information index (I = 0.3735) at the population level were high. AMOVA showed that most of the variation was within populations (71.74%), and only 28.26% of the variation was between populations. The neighbor-joining tree based on genetic distance revealed that significant genealogical structure existed throughout the examined range of the Bombay duck. The results demonstrated that SRAP marker was an effective tool for the assessment of genetic diversity in the Bombay duck. The results could be used for further protection of the germplasm resource of the Bombay duck.
Assuntos
Peixes/genética , Marcadores Genéticos , Variação Genética , Genética Populacional , Animais , China , Evolução Molecular , Loci Gênicos , Geografia , Técnicas de Amplificação de Ácido Nucleico , Filogenia , FilogeografiaRESUMO
The subsequent reproductive outcomes in couples with a history of recurrent pregnancy loss (RPL) associated with chromosome abnormalities or polymorphisms are generally not reported in China. Many RPL carrier couples have decided not to have children. The present study recorded the subsequent delivery, miscarriage, and unpregnancy outcomes of 113 RPL carrier couples and 226 non-carrier couples, and compared differences in reproductive outcomes between couples with different types of chromosome abnormalities or polymorphisms and chromosome normal couples. Our results showed that couples with RPL associated with parental chromosome abnormalities or polymorphisms did not have significantly lower live birth rates than non-carrier couples in China. These results suggest the current guidance given to Chinese RPL couples.
Assuntos
Aborto Habitual/genética , Aberrações Cromossômicas , Polimorfismo Genético , Reprodução/genética , Aborto Habitual/etiologia , Aborto Habitual/patologia , Adulto , China , Feminino , Humanos , Cariotipagem , Masculino , Idade Materna , Pessoa de Meia-Idade , GravidezRESUMO
The prevalence of microdeletions of azoospermia factor (AZF) among azoospermic Klinefelter's syndrome (KFS) patients shows conflicting data. We aimed to detect this frequency in a Northeast Chinese population, and to investigate the possible association between AZF microdeletions and KFS by comparison with previous conflicting reports. Eighty men affected with KFS and a random healthy control group comprising 60 fertile men and women were recruited. AZF microdeletions were detected by multiplex polymerase chain reaction using 9 specific sequence-tagged sites. Karyotype analyses were performed on peripheral blood lymphocytes using standard G-banding. Finally, azoospermia was confirmed in 77 men affected with KFS and no AZF microdeletions were found. Karyotype analysis revealed 1 patient with karyotype 47,XXY,inv (9) (p11, q13), and 2 with mosaic karyotypes (46,XX/47,XXY and 46,XY/47,XXY). All other patients had karyotype 47,XXY. Review of the literature showed that these results were similar to those of other regions of Northeast Asia, but differed from those obtained from Caucasian populations. Our results supported the proposal that AZF microdeletions and KFS result from separate genetic defects. The prevalence of AZF in azoospermic KFS patients varies among populations, and it might result from genetic drift or selective pressure. These results suggest that routine screening for classical AZF microdeletions among infertile azoospermic men with a 47,XXY karyotype might not be necessary in Northeast Chinese individuals. However, it remains imperative for patients considering assisted reproductive treatments, particularly for those with mosaic karyotypes.
Assuntos
Infertilidade Masculina/epidemiologia , Infertilidade Masculina/etiologia , Cariótipo Anormal , Azoospermia/epidemiologia , Azoospermia/etiologia , China/epidemiologia , Bandeamento Cromossômico , Deleção Cromossômica , Cromossomos Humanos Y , Humanos , Síndrome de Klinefelter/complicações , Síndrome de Klinefelter/genética , MasculinoRESUMO
The Swimming crab Portunus trituberculatus (Portunidae) is an important economically food species. To provide molecular markers for P. trituberculatus, we isolated and characterized polymorphic microsatellite markers. We developed a 5'-anchored genomic library of P. trituberculatus DNA, and derived 45 positive clones. We designed 30 pairs of primers from the sequences of these clones, and 10 of which were polymorphic. The loci were screened in 31 P. trituberculatus individuals; the number of alleles ranged from 2 to 5. The observed heterozygosity ranged from 0.20 to 0.49 and the expected heterozygosity ranged from 0.50 to 0.78. The polymorphism information content per locus ranged from 0.37 to 0.75. These polymorphic microsatellite markers may provide some useful information for the population genetic studies of swimming crab and other Portunus species.
Assuntos
Braquiúros/genética , Repetições de Microssatélites , Polimorfismo Genético , Alelos , Animais , Marcadores Genéticos , Biblioteca Genômica , HeterozigotoRESUMO
A pair of new universal 12S mitochondrial rRNA gene primers was designed through multiple alignment analysis of the mitochondrial tRNA(Phe) and the 5' region of 16S mitochondrial rRNA genes of different kinds of fishes. The primers were successfully used to amplify an expected product fragment of about 1.2 kb from various marine fish species, and the amplified DNA fragment was recognized to contain the complete 12S mitochondrial rRNA and tRNA(Val) genes, as well as a partial 16S mitochondrial rRNA gene of about 146 bp in length. The primers would facilitate the study of the species discrimination, population and evolution in marine fish species.
Assuntos
Primers do DNA/genética , Peixes/genética , Genes Mitocondriais , RNA Ribossômico/genética , Animais , Reação em Cadeia da Polimerase , RNA/genética , RNA MitocondrialRESUMO
Electron transfer flavoproteins (ETFs) are αß-heterodimers found in eukaryotic mitochondria and bacteria. Herein we report a full-length complementary DNA of a mud crab (Scylla paramamosain) ETF ß subunit (Scpa-ETFB) isolated with a homology cloning strategy. The complete complementary DNA of the Scpa-ETFB contains a 17-nt 5'-untranslated region, a 765-nt open reading frame encoding 254 amino acids, and a 248-nt 3'-untranslated region. The high identity of Scpa-ETFB with ETFB in other organisms indicated that Scpa-ETFB is a new member of the ETFB family. Although the conserved motif associated with flavin adenine dinucleotide binding is absent in Scpa-ETFB, the signature sequences of the ETF superfamily were identified. Using reverse transcriptase polymerase chain reaction, we detected the messenger RNA transcript of Scpa-ETFB in high levels in the tissues of the hepatopancreas, ovary, heart, and muscle. Phylogenetic analysis showed that Scpa-ETFB is most closely related to the ETFB genes of Caligus rogercresseyi and Lepeophtheirus salmonis. These results provided basic information for elucidating the molecular mechanism of energy production in the mud crab.
Assuntos
Proteínas de Artrópodes/genética , Braquiúros/genética , Flavoproteínas Transferidoras de Elétrons/genética , Sequência de Aminoácidos , Animais , Proteínas de Artrópodes/química , Proteínas de Artrópodes/metabolismo , Sequência de Bases , Braquiúros/metabolismo , Clonagem Molecular , Sequência Conservada , DNA Complementar/genética , Flavoproteínas Transferidoras de Elétrons/química , Flavoproteínas Transferidoras de Elétrons/metabolismo , Expressão Gênica , Dados de Sequência Molecular , Especificidade de Órgãos , Filogenia , Análise de Sequência de DNA , Homologia de Sequência de AminoácidosRESUMO
The small yellow croaker (Larimichthys polyactis) is a highly valued fish for human consumption found in the Western Pacific that was considered endangered until recently because of overfishing. We selected microsatellite markers for this species from markers developed for Miichthys miiuy, also of the family Sciaenidae. Among 43 markers polymorphic for M. miiuy, 11 were found to be polymorphic for L. polyactis. Characterization of these 11 loci was made based on 30 L. polyactis individuals collected by trawling in the Zhoushan Fishing Ground, Zhejiang Province, China. Total genomic DNA was isolated from fin clips. The number of alleles per locus ranged from 4 to 10, with a mean of 5.82, while the effective number of alleles ranged from 1.64 to 10.00, with a mean of 3.22. Observed and expected heterozygosities ranged from 0.17 to 0.72 and from 0.39 to 0.81, respectively. Significant deviation from Hardy-Weinberg equilibrium was found at four loci, after applying Bonferroni's correction. There was no significant association between any of the pairs of microsatellite loci, hence allelic variation at these loci was considered independent. These 11 polymorphic microsatellite loci will be useful for genetic diversity analysis and molecular-assisted breeding for L. polyactis.
Assuntos
Repetições de Microssatélites/genética , Perciformes/genética , Alelos , Animais , Variação Genética/genética , Heterozigoto , Polimorfismo Genético/genéticaRESUMO
Scylla paramamosain is a widespread and commercially important species of coastal marine crab. We identified 13 polymorphic microsatellite loci from a genome library constructed with 5'-anchored PCR method. Thirty-two S. paramamosain from the East China Sea were used to analyze the characteristics of these loci. The number of alleles per locus ranged from 3 to 8, with a mean of 5.923. Observed and expected heterozygosities ranged from 0.500 to 0.875 and from 0.500 to 0.859, respectively. Eleven of the 13 loci were highly polymorphic (polymorphic information content >0.5). All of the 13 novel loci were in Hardy-Weinberg equilibrium after Bonferroni's correction (P < 0.0038). There was no null allele, stuttering errors or evidence of allelic dropout in any of the loci analyzed by MICRO-CHECKER. According to pairwise tests, no significant linkage disequilibrium was found among the 13 loci (P < 0.0038, adjusted value). These novel developed microsatellites will be useful for studies of genetic variation, population structure, conservation genetics, and molecular-assisted selective breeding of S. paramamosain.
Assuntos
Braquiúros/genética , Repetições de Microssatélites/genética , Polimorfismo Genético/genética , Alelos , Animais , Desequilíbrio de Ligação/genética , Reação em Cadeia da PolimeraseRESUMO
The genetic diversity of Setipinna taty, which is commercially fished in the China Sea, was studied based on mitochondrial DNA control region sequences. PCR was used to amplify the control region fragment in 100 individuals of S. taty collected from Weihai (WH), Yantai (YT), Zhoushan (ZS), Xiangshan (XS), and Ninghai (NH) in China. A control region fragment of 656 bp was successfully sequenced in these 100 individuals. The A+T content of this S. taty control region was 71.7%; 172 variable sites and 62 haplotypes were found. Nucleotide diversity in the WH, YT, ZS, XS, and NH groups was 0.0228, 0.0247, 0.0441, 0.0126, and 0.0238, respectively. The haplotype diversity was 0.984, 0.911, 0.989, 0.926, and 0.979, respectively. Analysis of molecular variance showed that 97.95% of genetic variation was within populations, and only 2.05% among populations. The neighbor-joining phylogenetic tree obtained based on genetic distance showed that no significant genealogical structure exists throughout this range of S. taty. These results indicate no apparent geographical differentiation in the comparison of Yellow Sea and East China Sea populations of S. taty. Within the control region, we identified an extended termination-associated sequence domain, a central conserved sequence block domain and a conserved sequence block domain; insertions of short tandem repeat sequence segments were found at the 5' end of the control region.
Assuntos
DNA Mitocondrial/genética , Peixes/genética , Variação Genética , Animais , Sequência de Bases , Primers do DNA , Haplótipos , Dados de Sequência Molecular , Reação em Cadeia da PolimeraseRESUMO
We investigated the frequency and types of Y-chromosome microdeletions and chromosomal anomalies in non-obstructive azoospermic and severely oligozoospermic infertile males in northeastern China. The sample consisted of 519 infertile males (456 azoospermic, 63 severely oligozoospermic). PCR assays for Y-chromosome microdeletions and chromosome analysis were performed on all patients and controls. Array-comparative genomic hybridization was performed for three patients with chromosomal anomalies. Fifty-nine of 519 patients (11.37%) had Y-chromosome microdeletions. Microdeletions were found in 11.18% (51/456) of the non-obstructive azoospermic patients and in 12.7% (8/63) of the severely oligozoospermic patients. Eleven of 51 non-obstructive azoospermic patients with Y-chromosome microdeletions had multiple segmental deletions in the AZFb+c regions; four of these patients had chromosomal anomalies. Our sample from northeastern China had a higher frequency of microdeletions among severely oligozoospermic than among non-obstructive azoospermic males.