Search results for "Ploidy"
showing 10 items of 299 documents
Effects of inbreeding on a gregarious parasitoid wasp with complementary sex determination
2017
Inbreeding and inbreeding depression are processes in small populations of particular interest for a range of human activities such as animal breeding, species conservation or pest management. In particular, biological control programs should benefit from a thorough understanding of the causes and consequences of inbreeding because natural enemies experience repetitive bottlenecks during importation, laboratory rearing, and introduction. Predicting the effect of inbreeding in Hymenopteran parasitoid wasps, frequently used in biological control programs, is nonetheless a difficult endeavor. In haplodiploid parasitoids, the purge of deleterious alleles via haploid males should reduce genetic …
Doubled haploid production in onion (Allium cepa L.): from gynogenesis to chromosome doubling
2020
Bulb onion (Allium cepa L.) is an allogamous diploid (2n = 16) important for its culinary uses, nutritional value, and medicinal benefits. Despite its economic importance, onion yields and bulb quality are declining, emphasizing the need for new and improved strategies for maintaining and enhancing overall crop quality. Development of inbred lines in onion through traditional breeding is often difficult due to its biennial life cycle, inbreeding depression, and comparatively high heterozygosities. Moreover, genetic research in onion has been hampered by large nuclear genome size. In this regard, gynogenic doubled haploids promise several advantages over inbred lines in support of onion bree…
Chromosome numbers for the Italian flora: 11
2021
In this contribution, new chromosome data obtained on material collected in Italy are presented. It includes counts for Centaurea aegusae, Hieracium racemosum subsp. lucanum, H. australe subsp. australe, Lysimachia arvensis subsp. arvensis, Micromeria graeca subsp. graeca, and M. graeca subsp. consentina.
The evolutionary dynamics of adaptive virginity, sex-allocation, and altruistic helping in haplodiploid animals
2017
In haplodiploids, females can produce sons from unfertilized eggs without mating. However, virgin reproduction is usually considered to be a result of a failure to mate, rather than an adaptation. Here, we build an analytical model for evolution of virgin reproduction, sex-allocation, and altruistic female helping in haplodiploid taxa. We show that when mating is costly (e.g., when mating increases predation risk), virginity can evolve as an adaptive female reproductive strategy. Furthermore, adaptive virginity results in strongly divergent sex-ratios in mated and virgin queen nests ("split sex ratios"), which promotes the evolution of altruistic helping by daughters in mated queen nests. H…
Type of chromosome abnormality affects embryo morphology dynamics.
2016
Objective To study the differences in the cleavage time between types of embryo chromosomal abnormalities and elaborate algorithm to exclude aneuploid embryos according to the likelihood to be euploid. Design Retrospective cohort study. Setting University affiliated private center. Patient(s) Preimplantational genetic screening patients (n = 112) including cases of advanced maternal age, repeated implantation failure, and recurrent miscarriage. A total of 485 embryos were analyzed. Intervention(s) None. Main Outcome Measure(s) All biopsied embryos were cultured in an incubator with time-lapse technology, cleavage timing from insemination to day 3 and all kinetic parameters that have been de…
Transcriptomic behavior of genes associated with chromosome 21 aneuploidies in early embryo development.
2019
To analyze how chromosome 21 (HSA21) ploidy affects global gene expression of early human blastocysts.Prospective study.University-affiliated in vitro fertilization clinic.A total of 26 high-quality donated embryos from in vitro fertilization (IVF) patients: trisomy 21 (n = 8), monosomy 21 (n = 10), and euploid (n = 8) blastocysts.None.Blastocyst transcriptome changes and its associated functions.Trisomy 21, monosomy 21, and euploid blastocysts were classified by comparative genomic hybridization. The global transcriptome of whole blastocysts was analyzed with small cell number RNA sequencing, and they were compared to understand the gene expression behavior at early development and its imp…
Kinetics of the early development of uniparental human haploid embryos
2016
Objective: To describe morphokinetically the early development of human haploid parthenotes and androgenotes and to compare them with euploid embryos. Design: Experimental study of kinetics. Setting: University-affiliated private fertility center. Patient(s): Experimental haploid parthenotes and androgenotes. Intervention(s): Kinetic study of early development (up to eight cells) of 8 parthenotes, 10 androgenotes, and 20 euploid embryos. Main Outcome Measure(s): Timing of the first seven cleavages determined according to embryo origin, then calculation of the duration of the second and third cell cycles (cc2 and cc3) of whole embryos and individual cells. Result(s): Parthenotes and androgen…
Preimplantation genetic testing for aneuploidy in patients with partial X monosomy using their own oocytes: is this a suitable indication?
2019
Objective To describe the outcome of preimplantation genetic testing (PGT-A) using their own oocytes in patients with mosaic Turner Syndrome (MTS). The impact of the assisted reproduction technique (ART) performed (PGT-A or oocyte donation) and the type of absence of the X chromosome (total or partial) were considered. Design Retrospective observational multicenter study. Setting University-affiliated private in vitro fertilization center. Patient(s) Fifty-six patients with MTS with whom 65 ovarian stimulation cycles for PGT-A (fluorescence in situ hybridization/arrays-next generation sequencing) were performed. The study included 90 women with MTS and 20 women with pure Turner Syndrome (PT…
DNA demethylation caused By 5-Aza-2'-Deoxycytidine induces mitotic alterations and aneuploidy
2016
Aneuploidy, the unbalanced number of chromosomes in a cell, is considered a prevalent form of genetic instability and is largely acknowledged as a condition implicated in tumorigenesis. Epigenetic alterations like DNA hypomethylation have been correlated with cancer initiation/progression. Furthermore, a growing body of evidence suggests the involvement of epigenome-wide disruption as a cause of global DNA hypomethylation in aneuploidy generation. Here, we report that the DNA hypomethylating drug 5-aza-2′-deoxycytidine (DAC), affects the correct ploidy of nearly diploid HCT-116 human cells by altering the methylation pattern of the chromosomes. Specifically, we show that a DAC-induced reduc…
Targeting the chromosomal passenger complex subunit INCENP induces polyploidization, apoptosis and senescence in neuroblastoma
2019
Abstract Chromosomal passenger complex (CPC) has been demonstrated to be a potential target of cancer therapy by inhibiting Aurora B or survivin in different types of cancer including neuroblastoma. However, chemical inhibition of either Aurora B or survivin does not target CPC specifically due to off-target effects or CPC-independent activities of these two components. In a previous chromatin-focused siRNA screen, we found that neuroblastoma cells were particularly vulnerable to loss of INCENP, a gene encoding a key scaffolding component of the CPC. In this study, INCENP was highly expressed by neuroblastoma cells, and its expression decreased following retinoic acid–induced neuroblastoma …