Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Genetics and Reproduction”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 1,387 records · Page 77Linked to original sources
PubMed2004

Genetic stability in rice micropropagation.

An efficient clonal propagation procedure for six rice varieties cultivated in Argentina was developed by using shoot tip cultures, and the genetic stability of the micropropagated plants was verified by isozyme analysis. One week old seedlings obtained on MS medium were sectioned and subcultured on MS medium (0.75% agar) supplemented with different combination and concentrations of cytokinins (BAP and KIN) and auxins (2,4-D and NAA). After four weeks of culture, multiple shoots were obtained. The best response was observed on MS supplemented with BAP 5 mg l(-1). Shoot clumps were multiplied in MS liquid medium containing BAP 5 mg l(-1). Profuse rooting was obtained after transfer to MS medium lacking growth regulators and with sucrose 8% (w/v). Complete plants were successfully transferred to soil and grown to maturity. ADH and EST patterns of micropropagated rice plants showed polymorphisms compared with plants of the original varieties. However, the zymograms of the seed derived progeny of the micropropagated plants were similar to that of the original varieties. These results indicate the maintenance of the genetic stability in the sexual progeny of micropropagated plants.

Cells, Cultured↗
PubMed2004

[Preliminary gene-mapping of photoperiod-temperature sensitive genic male sterility in wheat (Triticum aestivum L.)].

The photoperiod-temperature sensitive genic male sterile (PTSGMS) line in wheat is important for the utilization of heterosis. The wheat line, BAU3338, is an excellent PTSGMS material identified in the recent years. In this study, its PTSGMS genes were mapped using molecular markers, SSR and ISSR. The result of molecular analysis showed that the two PTSGMS loci were identified and designated as ptms1 and ptms2, respectively. In addition, the genetic effect analysis indicated that the locus effect of ptms1 was 2-3 times larger than that of ptms2.

Chromosome Mapping↗
PubMed2004

Microrobots for in vitro fertilization applications.

The Micromanipulation and Micro-actuation Research Group at the LAB has activities related to biological and surgical applications. Concerning cells micromanipulation, our laboratory works in collaboration with the research team "Genetic and Reproduction" of the Besançon's hospital (France). The global final objective is the development of an automatic intra cytoplasmic sperm injection (ICSI) device in order to improve performances and ergonomics of current devices. In the future this new device will contain various modules: module for removal of cumulus cells, modules for characterization of oocytes, microinjection module, cells transport system. The first subsystem developed is a new single cell transport system. It consists in a so-called micropusher which pushes single cells without having contact with the external environment. This micropusher is a ferromagnetic particle (from 400 x 400 x 20 microm3 to 100 x 100 x 5 microm3) which follows the movement of a permanent magnet located under the biological medium. A 2D micro-positioning table moves this magnet under the glass slide. The pusher and cells positions are measured through an optical microscope with a CCD camera located above the biological medium. The second subsystem is developed to measure oocytes mechanical stiffness in order to sort them. We have then developed a micro/nano-force sensor based on the diamagnetic levitation principle: a glass tip end-effector (with 20 microm in diameter) is fixed on the equipment which is in levitation (0.5 mm in diameter, 100 mm in length). When a force is applied to the levitated glass tip, it moves to a new equilibrium position. Thanks to themeasurement of this displacement, the applied force can be measured. Since there is no contact and friction between the levitated tip and the fixed part, the resolution of this sensor is very high (10 nN).

Fertilization in Vitro↗
PubMed2004

[Analysis on the major gene and multigene mixed inheritance of wide compatibility gene in rice].

The intersubspecific hybrids between Indica and Japanica varieties are generally semi sterile, which limits the use of Indica-Japanica heterosis. Genetic study of wide compatibility gene (WCG) in rice helps to understand the mechanism of semi sterility and make it possible to overcome this phenomenon. In this study, the P1,P2,F1,B1,B2,and F2 of Indica-Japanica hybrid of 3037/02428 were analyzed by the major gene and minor gene mixed inheritance model. The research showed that Apart from single major gene, the WCG inheritance is also affected by minor genes. Not only major gene's effect on fertility but also minor gene's effect should be considered when utilize WCG to overcome semisterile between subspecies.

Crosses, Genetic↗
PubMed2004

Polymorphom of sexually different cucumber (Cucumis sativus L.) NIL lines.

Isolations of polymorphic sequences of two pairs of the NIL lines of cucumber (Cucumis sativus L.), which differ with respect to sex, were carried out using the subtraction hybridization methods of DSC (Differential Subtraction Chain) and GDDSC (Genetically Directed DSC). 266 DSC tags were isolated from the entire genome region, and 38 GDDSC tags were isolated from the region containing the sex genes. Based on the obtained results, the methods used may be considered highly effective. The attained sequences, like 11 AFLP clones obtained earlier [Witkowicz, J. et al. Cell. Mol. Biol. Lett. 8 (2003) 375-381], were characterized by analyzing their hybridization with differential (dhaom) and subtractive cDNA libraries (cDNAsubtractom) from 1- to 2- mm floral buds of the same lines, and by the sequencing of 28 tags. A high average degree of homology was found to exist in the genpolom to dhom and cDNAsubtractom, particularly in the case of "dominant" (when the tester used was a line in which the sex of the plants was dependent upon the dominant allele). This indicates a significant share of coding sequences in the polymorphic genomic tags as well as their share in flower formation. Many of these sequences originate from the sex gene region. Analysis of the sequenced tags showed their interesting composition, including many organelle sequences which transferred into the nucleus, and coding.

Cloning, Molecular↗
PubMed2005

Human gene banks.

Explore the source record for details and available documents.

Biological Specimen Banks↗
PubMed2005

Postmating-prezygotic isolation is not an important source of selection for reinforcement within and between species in Drosophila pseudoobscura and D. persimilis.

Most work on adaptive speciation to date has focused on the role of low hybrid fitness as the force driving reinforcement (the evolution of premating isolation after secondary contact that reduces the likelihood of matings between populations). However, recent theoretical work has shown that postmating, prezygotic incompatibilities may also be important in driving premating isolation. We quantified premating, postmating-prezygotic, and early postzygotic fitness effects in crosses among three populations: Drosophila persimilis, D. pseudoobscura USA (sympatric to D. persimilis), and D. pseudoobscura Bogotá (allopatric to D. persimilis). Interspecific matings were more likely to fail when they involved the sympatric populations than when they involved the allopatric populations, consistent with reinforcement. We also found that failure rate in sympatric mating trials depended on whether D. persimilis females were paired with D. pseudoobscura males or the reverse. This asymmetry most likely indicates differences in discrimination against heterospecific males by females. By measuring egg laying rate, fertilization success and hatching success, we also compared components of postmating-prezygotic and early postzygotic isolation. Postmating-prezygotic fitness costs were small and not distinguishable between hetero- and conspecific crosses. Early postzygotic fitness effects due to hatching success differences were also small in between-population crosses. There was, however, a postzygotic fitness effect that may have resulted from an X-linked allele found in one of the two strains of D. pseudoobscura USA. We conclude that the postmating-prezygotic fitness costs we measured probably did not drive premating isolation in these species. Premating isolation is most likely driven in sympatric populations by previously known hybrid male sterility.

Adaptation, Physiological↗
PubMed1991

RU-486: the "abortion pill".

A report sent by the Vatican to bishops' conferences throughout the world calls RU-486, the so-called abortion pill currently available in France, "a new, serious threat to human life." The report was developed at the Vatican's request by Gonzalo Herranz, a Spanish bioethicist. A cover letter to bishops' conferences from Cardinal Alfonso Lopez Trujillo, president of the Pontifical Council for the Family, suggested that the report be used "to resist the introduction of the abortion pill RU-486 into your country." Related to TU-486 and to new terminology some use to characterize its non-surgical approach to abortion is an intention "to amoralize and thereby place the transmission of human life into an ethically neutral terrain and reduce it to pure biology," says the report. The report discusses possible future uses of RU-486 as a contraceptive, stating: "Women would no longer have to worry themselves about whether they have conceived or not. Each month they would proceed to clean out their uterus chemically." The report refers to RU-486 as "a technical step forward in an area that did not need it." It says, "The abortion pill favors a woman's privacy and secret, but it condemns her to solitude." The English text from the Vatican follows.

Abortion, Induced↗
PubMed2005

Morphological variations in Phlebotomus argentipes (Diptera: Psychodidae) Annandale and Brunetti.

Morphological variations were observed in Phlebotomus argentipes, the vector for visceral leishmaniasis reported from the endemic states of Bihar, West Bengal and Uttar Pradesh. The taxonomic features distinguishing vector and nonvector species of P. argentipes were relative length of ascoid and antennal segment IV. Three morphotypes were characterized as <0.4, = 0.4 and >0.4 respectively. Other characteristics of wing width, wing length, eye, style, antennal segment III, IV, V was found statistically significant (p<0.05) and eleven other morphological measurements were not significant. This study suggests three different morphotypes of P. argentipes in these three endemic states. The genetic and reproductive isolation among such morphotypes will establish the variability in further studies.

Animals↗