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1.
It is well known that dopaminergic genes affect the development of attention deficit hyperactivity disorder (ADHD) in various populations. Many studies have shown that variable number tandem repeats (VNTRs) located within the 3′-untranslated region of DAT1 and in exon 3 of DRD4 are associated with ADHD development; however, these results were inconsistent. Therefore, we investigated the genetic association between two VNTRs and ADHD in Korean children. We determined the VNTRs using PCR. We examined genotype and allele frequency differences between the experimental and control groups, along with the odds ratios, using Chi square and exact tests. We observed a significant association between the children with ADHD and the control group in the 10R/10R genotype of DAT1 VNTRs (p?=?0.025). In addition, the 11R allele of DAT1 VNTRs showed a higher frequency in the control group than in the ADHD group (p?=?0.023). Also, the short repeat (without 11R) and long repeat alleles (including 11R) were associated with ADHD (p?<?0.05). The analysis of DRD4 VNTRs revealed that the 2R allele is associated with ADHD (p?=?0.025). A significant result was also observed in long and short repeats (p?<?0.05). Additionally, ADHD subtypes showed that the DRD4 VNTRs are associated with combined and hyperactive-impulsive subtype groups (p?<?0.05). Therefore, our results suggest that DAT1 VNTRs and DRD4 VNTRs play a role in the genetic etiology of ADHD in Korean children.  相似文献   

2.
Forsthoefel NR  Vernon DM 《Planta》2011,233(2):423-431
Plant intracellular ras-group-related leucine-rich repeat proteins (PIRLs) are a novel class of plant leucine-rich repeat (LRR) proteins structurally related to animal ras-group LRRs involved in cell signaling and gene regulation. Gene knockout analysis has shown that two members of the Arabidopsis thaliana PIRL gene family, PIRL1 and PIRL9, are redundant and essential for pollen development and viability: pirl1;pirl9 microspores produced by pirl1/PIRL1;pirl9 plants consistently abort just before pollen mitosis I. qrt1 tetrad analysis demonstrated that the genes become essential after meiosis, during anther stage 10. In this study, we characterized the phenotype of pirl1;pirl9 pollen produced by plants heterozygous for pirl9 (pirl1;pirl9/PIRL9). Alexander’s staining, scanning electron microscopy, and fluorescence microscopy indicated that pirl1;pirl9 double mutants produced by pirl9 heterozygotes have a less severe phenotype and more variable morphology than pirl1;pirl9 pollen from pirl1/PIRL1;pirl9 plants. Mutant pollen underwent developmental arrest with variable timing, often progressing beyond pollen mitosis I and arresting at the binucleate stage. Thus, although the pirl1 and pirl9 mutations act post-meiosis, the timing and expressivity of the pirl1;pirl9 pollen phenotype depends on the pirl9 genotype of the parent plant. These results suggest a continued requirement for PIRL1 and PIRL9 beyond the initiation of pollen mitosis. Furthermore, they reveal a modest but novel sporophytic effect in which parent plant genotype influences a mutant phenotype expressed in the haploid generation.  相似文献   

3.
The distribution of polymorphic variants in the MTHFR, MTR and MTRR genes in the contingents of patients with nonsyndromic cleft lip and/or palate (NSCL/P), their mothers, and healthy individuals from Ukraine’s western region was evaluated. It was shown that the presence of the homozygous MTHFR 677TT genotype might lead to a threefold increase in the risk of CL/P; mothers carrying the MTHFR 677TT genotype had a twofold increase in the risk of giving birth to a child with CL/P compared to homozygous carriers of MTHFR 677CC (OR = 3.3 and OR = 1.92, respectively). The presence of the heterozygous genotype MTR 2756AG can lead to a 1.5-fold increase in the risk of CL/P compared to the 2765AA genotype (OR = 1.48). The heterozygous genotype MTRR 66AG is associated with a 5-fold risk of CL/P (OR = 5.56); mothers carrying this genotype had a 2.6-fold increase in the risk of giving birth to a child with CL/P (OR = 2.6). The prevalence of the MTRR 66G allelic variant among inhabitants of Ukraine’s western region was higher compared to the MTRR 66A allelic variant (wild type); and the MTRR 66GG genotype frequency among CL/P patients was significantly lower compared to the control group.  相似文献   

4.
5.
Our studies have shown that the genotype and allele frequencies of polymorphisms G(?1607)GG of MMP1 gene, C(?1562)T of MMP9 gene, and A(?82)G of MMP12 gene do not significantly differ in the samples of chronic obstructive pulmonary disease (COPD) patients (N = 318) and healthy controls (N = 319) dwelling in Bashkortostan Republic. However, association of (?1562)T allele of the MMP9 gene with the severity of COPD disease progression has been revealed. In COPD patients at stage 4 of the disease, the frequency of allele T was significantly higher that in patients with the stages 2 and 3 (15.89% versus 8.38%; χ2 = 7.804; d.f. = 1; P = 0.005; OR = 2.06 95% CI 1.22–3.49). The distribution of the genotype frequencies of C(?1562)T polymorphism of MMP9 gene significantly differed between the patients with various COPD severity (χ2 = 9.849; d.f. = 2; P = 0.007). The individuals with rare genotype TT were revealed only among patients with severe COPD form (3.97% versus 0%; χ2 = 4.78; P = 0.029; P cor = 0.058). Analysis of this polymorphism in patients with early COPD onset (younger than 55 years old) has shown a significant increase in the allele T frequency in the group of patients with severe COPD (stage 4 according to GOLD) compared to the patients of the same age but with less severe COPD progression (χ2 = 5.26; d.f. = 1; P = 0.022). As the major clinical characteristics of stage 4 COPD is the development of pulmonary emphysema as well as bronchial walls deformation, we suggest that the increased expression of MMP9 gene caused by genetic polymorphism in the gene promoter is important in the early development of serious complications of the disease.  相似文献   

6.
Two repeated DNA sequences isolated from a partial genomic DNA library of Helianthus annuus, p HaS13 and p HaS211, were shown to represent portions of the int gene of a Ty3 /gypsy retroelement and of the RNase-Hgene of a Ty1 /copia retroelement, respectively. Southern blotting patterns obtained by hybridizing the two probes to BglII- or DraI-digested genomic DNA from different Helianthus species showed p HaS13 and p HaS211 were parts of dispersed repeats at least 8 and 7 kb in length, respectively, that were conserved in all species studied. Comparable hybridization patterns were obtained in all species with p HaS13. By contrast, the patterns obtained by hybridizing p HaS211 clearly differentiated annual species from perennials. The frequencies of p HaS13- and p HaS211-related sequences in different species were 4.3x10(4)-1.3x10(5) copies and 9.9x10(2)-8.1x10(3) copies per picogram of DNA, respectively. The frequency of p HaS13-related sequences varied widely within annual species, while no significant difference was observed among perennial species. Conversely, the frequency variation of p HaS211-related sequences was as large within annual species as within perennials. Sequences of both families were found to be dispersed along the length of all chromosomes in all species studied. However, Ty3 /gypsy-like sequences were localized preferentially at the centromeric regions, whereas Ty1/ copia-like sequences were less represented or absent around the centromeres and plentiful at the chromosome ends. These findings suggest that the two sequence families played a role in Helianthusgenome evolution and species divergence, evolved independently in the same genomic backgrounds and in annual or perennial species, and acquired different possible functions in the host genomes.  相似文献   

7.
To test the M31R and R335C polymorphisms of the Il8RA gene for association with atopic bronchial asthma (BA), the allele and genotype frequency distributions of the polymorphisms were studied in Russian patients from Moscow and Buryat patients from Ulan-Ude. The study involved two Russian groups, one including 291 DNA samples of patients with atopic BA, and the other, 266 DNA samples of healthy people. The two Buryat groups included 124 and 152 DNA samples from patients with atopic BA and healthy people, respectively. The M31R polymorphism proved to be associated with atopic BA in Russians. Allele Arg and genotype Met/Arg suggested a higher risk of BA (OR = 4.45, P = 0.003 and OR = 4.58, P = 0.003, respectively), while allele Met and genotype Met/Met were associated with a lower risk (OR = 0.22, P = 0.003 and OR = 0.22, P = 0.003, respectively). The R335C polymorphism was not associated with atopic BA in Russians and was in Buryats. Allele Arg and homozygous genotype Arg/Arg suggested a higher risk of the disease (OR = 3.06, P = 0.030 and OR = 3.20, P = 0.027, respectively), while allele Cys and genotype Arg/Cys suggested a lower risk (OR = 0.33, P = 0.030 and OR = 0.31, P = 0.027, respectively). The results support the role of the IL8RA gene in atopic BA.  相似文献   

8.
To understand the molecular basis of broad-spectrum resistance to rice blast, fine-scale mapping of the two blast resistance (R) genes, Pi9( t) and Pi2( t), was conducted. These two genes were introgressed from different resistance donors, previously reported to confer resistance to many blast isolates in the Philippines, and were mapped to an approximately 10-cM interval on chromosome 6. To further test their resistance spectrum, 43 blast isolates collected from 13 countries were used to inoculate the Pi2( t) and Pi9( t) plants. Pi9( t)-bearing lines were highly resistant to all isolates tested, and lines carrying Pi2( t) were resistant to 36 isolates, confirming the broad-spectrum resistance of these two genes to diverse blast isolates. Three RAPD markers tightly linked to Pi9( t) were identified using the bulk segregant analysis technique. Twelve positive bacterial artificial chromosome (BAC) clones were identified and a BAC contig covering about 100 kb was constructed when the Pi9( t) BAC library was screened with one of the markers. A high-resolution map of Pi9( t) was constructed using BAC ends. The Pi2( t) gene was tightly linked to all of the Pi9( t) markers in 450 F(2) plants. These data suggest that Pi9( t) and Pi2( t) are either allelic or tightly linked in an approximately 100-kb region. The mapping results for Pi9( t) and Pi2( t) provide essential information for the positional cloning of these two important blast resistance genes in rice.  相似文献   

9.
Paratelmatobius and Scythrophrys are leptodactylid frogs endemic to the Brazilian Atlantic forest and their close phylogenetic relationship was recently inferred in an analysis that included Paratelmatobius sp. and S. sawayae. To investigate the interspecific relationships among Paratelmatobius and Scythrophrys species, we analyzed a mitochondrial region (approximately 2.4 kb) that included the ribosomal genes 12S and 16S and the tRNAval in representatives of all known localities of these genera and in 54 other species. Maximum parsimony inferences were done using PAUP* and support for the clades was evaluated by bootstrapping. A cytogenetic analysis using Giemsa staining, C-banding and silver staining was also done for those populations of Paratelmatobius not included in previous cytogenetic studies of this genus in order to assess their karyotype differentiation. Our results suggested Paratelmatobius and Scythrophrys formed a clade strongly supported by bootstrapping, which corroborated their very close phylogenetic relationship. Among the Paratelmatobius species, two clades were identified and corroborated the groups P. mantiqueira and P. cardosoi previously proposed based on morphological characters. The karyotypes of Paratelmatobius sp. 2 and Paratelmatobius sp. 3 described here had diploid chromosome number 2n = 24 and showed many similarities with karyotypes of other Paratelmatobius representatives. The cytogenetic data and the phylogenetic analysis allowed the proposal/corroboration of several hypotheses for the karyotype differentiation within Paratelmatobius and Scythrophrys. Namely the telocentric pair No. 4 represented a synapomorphy of P. cardosoi and Paratelmatobius sp. 2, while chromosome pair No. 5 with interstitial C-bands could be interpreted as a synapomorphy of the P. cardosoi group. The NOR-bearing chromosome No. 10 in the karyotype of P. poecilogaster was considered homeologous to chromosome No. 10 in the karyotype of Scythrophrys sp., chromosome No. 9 in the karyotype of Paratelmatobius sp. 1, chromosome No. 8 in the karyotypes of Paratelmatobius sp. 2 and of Paratelmatobius sp. 3, and chromosome No. 7 in the karyotype of P. cardosoi. A hypothesis for the evolutionary divergence of these NOR-bearing chromosomes, which probably involved events like gain in heteochromatin, was proposed.  相似文献   

10.
The New World primate Aotus nancymaae has been recommended by the World Health Organization (WHO) as a model for evaluation of malaria vaccine candidates, given its susceptibility to experimental infection with the human malaria parasites Plasmodium falciparum and Plasmodium vivax. We present here the nucleotide sequences of the complete cDNA of MHC-DQA1 and of the polymorphic exon 2 segments of MHC-DQB1/DQB2. In a group of three nonrelated animals captured in the wild, five alleles of MHC-DQA1 could be identified. They all belong to one lineage, namely Aona-DQA1*27. This lineage has not been described in any other New World monkey species studied. In a group of 19 unrelated animals, 14 Aona-DQB1 alleles could be identified which are grouped into the two lineages Aona-DQB1*22 and Aona-DQB1*23. These lineages have been described previously in the common marmoset and cotton-top tamarin. In addition, two Aona-DQB2 sequences could be identified which are highly similar to HLA-DQB2 sequences. Essential amino acid residues contributing to MHC DQ peptide binding pockets number 1 and 4 are conserved or semi-conserved between HLA-DQ and Aona-DQ molecules, indicating a capacity to bind similar peptide repertoires. These results fully support the use of Aotus monkeys as an animal model for evaluation of future subunit vaccine candidates.  相似文献   

11.
The grain color of wheat affects not only the brightness of flour, but also tolerance to preharvest sprouting. Grain color is controlled by dominant R-1 genes located on the long arm of hexaploid wheat chromosomes 3A, 3B, and 3D (R-A1, R-B1, and R-D1, respectively). The red pigment of the grain coat is composed of catechin and proanthocyanidin (PA), which are synthesized via the flavonoid biosynthetic pathway. We isolated the Tamyb10-A1, Tamyb10-B1, and Tamyb10-D1 genes, located on chromosomes 3A, 3B, and 3D, respectively. These genes encode R2R3-type MYB domain proteins, similar to TT2 of Arabidopsis, which controls PA synthesis in testa. In recessive R-A1 lines, two types of Tamyb10-A1 genes: (1) deletion of the first half of the R2-repeat of the MYB region and (2) insertion of a 2.2-kb transposon belonging to the hAT family. The Tamyb10-B1 genes of recessive R-B1 lines had 19-bp deletion, which caused a frame shift in the middle part of the open reading frame. With a transient assay using wheat coleoptiles, we revealed that the Tamyb10 gene in the dominant R-1 allele activated the flavonoid biosynthetic genes. We developed PCR-based markers to detect the dominant/recessive alleles of R-A1, R-B1, and R-D1. These markers proved to be correlated to known R-1 genotypes of 33 varieties except for a mutant with a single nucleotide substitution. Furthermore, double-haploid (DH) lines derived from the cross between red- and white-grained lines were found to necessarily carry functional Tamyb10 gene(s). Thus, PCR-based markers for Tamyb10 genes are very useful to detect R-1 alleles.  相似文献   

12.
Using bioinformatics analysis, the homologs of genes Sr33 and Sr35 were identified in the genomes of Triticum aestivum, Hordeum vulgare, and Triticum urartu. It is known that these genes confer resistance to highly virulent wheat stem rust races (Ug99). To identify amino acid sites important for this resistance, the found homologs were compared with the Sr33 and Sr35 protein sequences. It was found that sequences S5DMA6 and E9P785 are the closest homologs of protein RGAle, a Sr33 gene product, and sequences M7YFA9 (CNL-C) and F2E9R2 are homologs of protein CNL9, a Sr35 gene product. It is assumed that the homologs of genes Sr33 and Sr35, which were obtained from the wild relatives of wheat and barley, can confer resistance to various forms of stem rust and can be used in the future breeding programs aimed at improvement of national wheat varieties.  相似文献   

13.
Rhizoctonia solani and Phytophthora capsici are two of the most destructive phytopathogens occurring worldwide and are only partly being managed by traditional control strategies. Fluorescent Pseudomonas isolates PGC1 and PGC2 were checked for the antifungal potential against R. solani and P. capsici. Both the isolates were screened for the ability to produce a range of antifungal compounds. The results of this study indicated the role of chitinase and β-1,3-glucanase in the inhibition of R. solani, however, antifungal metabolites of a non-enzymatic nature were responsible for inhibition of P. capsici. The study confirmed that multiple and diverse mechanisms are adopted by the same antagonist to suppress different phytopathogens, as evidenced in case of R. solani and P. capsici.  相似文献   

14.
New combinations are proposed in anticipation of the Polygonaceae treatment in the forthcoming volume of Intermountain Flora: Polygonum kelloggii var. esotericum, P. kelloggii var. watsonii , Rumex densiflorus var. pycnanthus , R. salicifolius var. utahensis, and R. occidentalis var. tomentellus. Typifications are proposed to facilitate ongoing studies in Polygonaceae and to maintain current usage.  相似文献   

15.
16.
This study was conducted in order to identify quantitative trait loci (QTLs) for the in vitro culture response of winter rye (Secale cereale L.) immature embryos and immature inflorescences. A genetic linkage map comprising 67 SSRs, 9 ISSRs, 13 SAMPLs, 7 RAPDs, 2 SCARs and one EST marker was created based on the analyses of 102 recombinant inbred lines from the cross between lines L318 (which has a good response in tissue cultures) and L9 (which is unable to regenerate plants from somatic tissues and anthers). The map spans 979.2 cM, and the average distance between markers is 9.9 cM. Two characteristics were evaluated: callus induction (CI) and somatic embryogenesis ability (SE). They were expressed as the percentage of immature embryos/inflorescences producing callus (designated ECI/ICI) and the percentage of explants producing somatic embryos (ESE/ISE). All the analysed traits showed continuous variation in the mapping population but a non-normal frequency distribution. We identified nine putative QTLs controlling the tissue culture response of rye, explaining up to 41.6% of the total phenotypic variation: two QTLs for ECI — eci-1, eci-2; 4 for ESE — ece-1, ese-2, ese-3, ese-4; 2 for ICI — ici-1, ici2; and 1 for ISE — ise-1. They were detected on chromosomes 1R, 4R, 5R, 6R and 7R.  相似文献   

17.
Three Australian native animal species yielded 60 samples composed of three indigenous ticks. Hosts included twelve koalas, two echidnas and one wombat from Victoria, and ticks were of the species Ixodes tasmani (n = 42), Bothriocroton concolor (n = 8) and B. auruginans (n = 10), respectively. PCR screening and sequencing detected a species of Coxiella, sharing closest sequence identity to C. burnetii (>98%), in all B. auruginans, as well as a species of Rickettsia, matching closest to R. massiliae, in 70% of the same samples. A genotype sharing closest similarity to Rickettsia bellii (>99%) was identified in three female B. concolor collected from one of the echidnas. Three samples of I. tasmani, taken from three koalas, yielded different genotypes of Rickettsiella. These results represent the first detection of the three genera in each tick species and identify a high level of previously undetected bacterial diversity in Australian ticks.  相似文献   

18.
19.
Tay ST  Chai HC  Na SL  Ng KP 《Mycopathologia》2005,159(3):325-329
The genotypes of 221 recent isolates of Candida albicans from various clinical specimens of 213 patients admitted to the University Malaya Medical Centre, Malaysia was determined based on the amplification of a transposable intron region in the 25 S rRNA gene. The analyses of 178 C. albicansisolated from nonsterile clinical specimens showed that they could be classified into three genotypes: genotype A (138 isolates), genotype B (38 isolates) and genotype C (2 isolates). The genotyping of 43 clinical isolates from sterile specimens showed that they belonged to genotype A (29 isolates), genotype B (10 isolates), genotype C (2 isolates) and genotype D (2 isolates). The overall distribution of C. albicans genotypes in sterile and nonsterile specimens appeared similar, with genotype A being the most predominant type. This study reported the identification of C. dubliniensis (genotype D) in 2 HIV-negative patients with systemic candidiasis, which were missed by the routine mycological procedure. The study demonstrated the genetic diversity of clinical isolates of C. albicans in Malaysia.  相似文献   

20.
Three constructs harbouring novel Bacillus thuringiensis genes (Cry1C, Cry2A, Cry9C) and bar gene were transformed into four upland cotton cultivars, Ekangmian10, Emian22, Coker201 and YZ1 via Agrobacterium-mediated transformation. With the bar gene as a selectable marker, about 84.8 % of resistant calli have been confirmed positive by polymerase chain reaction (PCR) tests, and totally 50 transgenic plants were regenerated. The insertions were verified by means of Southern blotting. Bioassay showed 80 % of the transgenic plantlets generated resistance to both herbicide and insect. We optimized conditions for improving the transformation efficiency. A modified in vitro shoot-tip grafting technique was introduced to help entire transplantation. This result showed that bar gene can replace antibiotic marker genes (ex. npt II gene) used in cotton transformation.  相似文献   

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