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The Asian corn borer, Ostrinia furnacalis enters diapause as fully grown larvae. Owing to geographical variation in photoperiodic control of diapause, the subtropical strain from Hefei city (HF) enters diapause in response to short daylengths, whereas the tropical strain from Ledong county (LD) exhibits almost no diapause under the same conditions. The two strains were used in crosses to study the inheritance of diapause. The HF strain showed a typical long-day response with a critical daylength of approximately14.97 h at 22 °C, 14.60 h at 25 °C and 13.68 h at 28 °C. The LD strain showed weak photoperiodic responses at 22 and 25 °C; and the F1 progeny also showed a long-day response with significantly shorter critical daylength compared with the HF strain. However, the LD × HF (F × M) crosses had significantly longer critical daylengths than HF × LD crosses, indicating a sexual bias in the inheritance of diapause induction, with the male parent having more influence on the F1 progeny. The critical daylength in a backcross to HF was significantly longer than a backcross to LD. Whether the inheritance of diapause fits an additive hypothesis or not depended on photoperiod, with results from different photoperiods showing additive inheritance or incomplete dominance of either diapause or non-diapause. Unlike diapause induction, the duration of diapause for reciprocal crosses was equally influenced by each parent, suggesting that diapause incidence and maintenance are controlled by separate systems in O. furnacalis. [ABSTRACT FROM AUTHOR]

Many species exhibit transgenerational plasticity by which environmental cues experienced by either parent can be transmitted to their offspring, resulting in phenotypic variants in offspring to match ancestral environments. However, the manner by which paternal experiences affect offspring plasticity through epigenetic inheritance in animals generally remains unclear. In this study, we examined the transgenerational effects of population density on phase-related traits in the migratory locust Locusta migratoria. Using an experimental design that explicitly controls genetic background, we found that the effects of crowd or isolation rearing on phase plasticity could be inherited to the offspring. The isolation of gregarious locusts resulted in reduced weight in offspring eggs and altered morphometric traits in hatchlings, whereas crowding of solitarious locusts exhibited opposite effects. The consequences of density changes were transmitted by both maternal and paternal inheritance, although the expression of paternal effects was not as pronounced as that of maternal effects. Prominent expression of heat-shock proteins (Hsps), such as Hsp90, Hsp70 and Hsp20.6, could be triggered by density changes. Hsps were significantly upregulated upon crowding but downregulated upon isolation. The variation in parental Hsp expression was also transmitted to the offspring, in which the pattern of inheritance was consistent with that of phase characteristics. These results revealed a paternal effect on phase polyphenism and Hsp expression induced by population density, and defined a model system that could be used to study the paternal epigenetic inheritance of environmental changes. [ABSTRACT FROM AUTHOR]

Intake of milk fat in human nutrition is important because of unsaturated and especially essential fatty acids (FAs), linoleic and α-linolenic acid, and conjugated linoleic acid (CLA), which is found only in meat and milk of ruminants. The objective of our study was to investigate the effect of paternal bulls on fatty acids composition in milk fat of dairy cows of different breeds. The milk samples were taken in total from 299 dairy cows from 11 dairy farms. In experiment Holstein (H, n = 105), Red Holstein (R, n = 120) and Pinzgau (P, n = 74) breeds originated from different bulls were used. Individual milk samples were analyzed for fatty acids in milk fat using gas chromatography (apparatus GC Varian 3800, Techtron, USA), using FID detector in capillary column Omegawax 530; 30 m. In the chromatography records there were identified 54 fatty acids inclusive of particular isomers. Their relative proportions were expressed in percent's (%). Among the studied breeds, the highest content of conjugated linoleic acid (CLA) – 0.67%, essential FAs (EFA) – 2.98%, monounsaturated FAs (MUFA) – 25.84% and the lowest atherogenic index (AI) – 3.10 was at breed P. Within this breed there was high variability and daughters of bull COS1 achieved significant above-average values of CLA content 1.07%, EFA 3.71%, MUFA 29.93% and under breed average AI = 2.40. The group of daughters of NOB3 was significant lower in CLA, 0.50% as compared with an average of P breed. . From the breed H bull MTY2 showed significantly higher value of 0.62% CLA, EFA 3.42%, 34.29% MUFA and lower value of AI, 1.9 as compared to H breed average. Statistically significantly lower levels of CLA 0.29% and 21.46% MUFA and higher AI 3.72 in milk fat of his daughters, bull STY3 may be considered as potential worser of these properties. At the breed R bull MOR506 showed in compar to the breed average significantly higher value of the EFA 3.80% and also the higher content of CLA 0.50% and MUFA 25.09%, resulting in statistically significant lower AI = 2.91. Bull MOR506 could be considered as potential improver of milk fat composition. The above described variability in the composition of milk fat of dairy cows and the subsequent relationships between these values suggest that the selection of the bull according to the fatty acid composition of milk fat may be considered. [ABSTRACT FROM AUTHOR]

Newly discovered non-genetic mechanisms break the link between genes and inheritance, thereby also raising the possibility that previous mating partners could influence traits in offspring sired by subsequent males that mate with the same female ('telegony'). In the fly Telostylinus angusticollis, males transmit their environmentally acquired condition via paternal effects on offspring body size. We manipulated male condition, and mated females to two males in high or low condition in a fully crossed design. Although the second male sired a large majority of offspring, offspring body size was influenced by the condition of the first male. This effect was not observed when females were exposed to the first male without mating, implicating semen-mediated effects rather than female differential allocation based on pre-mating assessment of male quality. Our results reveal a novel type of transgenerational effect with potential implications for the evolution of reproductive strategies. [ABSTRACT FROM AUTHOR]

Environmental effects on gene expression and offspring development can be mediated by epigenetic modifications. It is well established that maternal diet influences DNA methylation patterns and phenotypes in the offspring; however, the epigenetic effects of paternal diet on developing offspring warrants further investigation. Here, we examined how a prepubertal methionine-enriched paternal diet affected sperm DNA methylation and its subsequent effects on embryo gene expression. Three treatment and three control rams were bred to seven ewes, and blastocysts were flushed for RNA extraction. Semen was collected from all rams and submitted for reduced representation bisulfite sequencing analysis. In total, 166 differentially methylated cytosines were identified in the sperm from treatment versus control rams. Nine genes were found to be differentially expressed in embryos produced from treatment versus control rams, and seven differentially methylated cytosines in the sperm were found to be highly correlated with gene expression in the embryos. Our results demonstrate that sperm methylation differences induced by diet may influence fetal programming., (© The Author(s) 2023. Published by Oxford University Press.)

Abstract: Many fish of aquacultural importance including sturgeon and paddlefish have a history of polyploidy in their evolutionary lineages. Spontaneous autopolyploids have been detected in several sturgeon species in culture despite the fact that the induction of triploidy is not a management tool in farming sturgeon for meat and caviar. In 2010, we discovered two female spontaneous autopolyploid white sturgeon (Acipenser transmontanus) on a commercial caviar farm that had successfully produced offspring of intermediate ploidy in crosses with normal males. Here we use flow cytometry and microsatellite genotyping to screen a second aquaculture program for the presence of spontaneous autopolyploids. Flow cytometry of female parents and their progeny in the 2011 year class created by the Kootenai River white sturgeon conservation aquaculture program revealed that wild caught females used as dams possessed normal ploidy (8N). Five of ten families sampled from the 2011year class contained spontaneous autopolyploids possessing DNA content consistent with dodecaploidy (12N). The percent of autopolyploid individuals sampled ranged from 0 to 33% per family, and the total number of spontaneous autopolyploids in the 2011 year class was 12/150 (8%). Microsatellites were not useful in detecting spontaneous autopolyploids in the conservation aquaculture program due to low levels of genetic diversity in the endangered Kootenai River population. The two families with the highest incidence of spontaneous autopolyploids (33% and 26% of offspring sampled) were sired by a single male, suggesting a paternal effect on the generation of spontaneous autopolyploids in white sturgeon. [Copyright &y& Elsevier]

The ability of females to adaptively influence offspring phenotype via maternal effects is widely acknowledged, but corresponding nongenetic paternal effects remain unexplored. Males can adjust sperm phenotype in response to local conditions, but the transgenerational consequences of this plasticity are unknown. We manipulated paternal density of a broadcast spawner (Styela plicata, a solitary ascidean) using methods shown previously to alter sperm phenotype in the field, then conducted in vitro fertilizations that excluded maternal effects and estimated offspring performance under natural conditions. Offspring sired by males from low-density experimental populations developed faster and had a higher hatching success than offspring sired by males living in high densities. In the field, offspring survived relatively better when their environment matched their father's, raising the possibility that fathers can adaptively influence the phenotype of their offspring according to local conditions. As the only difference between offspring is whether they were artificially fertilized by sperm from males kept in high- vs. low-density cages, we can unequivocally attribute any differences in offspring performance to an environmentally induced paternal effect. Males of many species manipulate the phenotype of their sperm in response to sperm competition: our results show this plasticity can influence offspring fitness, potentially in adaptive ways, raising the possibility that adaptive nongenetic paternal effects may be more common than previously thought. [ABSTRACT FROM AUTHOR]

Inheritance of non-genetic factors permits ancestral environmental history to inform the development of subsequent generations. This form of soft inheritance has been shown in mammals, yet the molecular underpinnings of this phenomenon are poorly understood. In the present article, we focus on gametic inheritance of non-genetic factors, utilizing examples of paternal transmission to explore the core issues that need to be addressed in order to gain greater insight into the molecular mechanisms. Three essential processes are identified: (i) how the environment affects the germline to establish an altered molecular milieu, (ii) the molecular nature of the inherited mark, and (iii) how this affects genome function in the developing embryo to elicit an alternative developmental outcome. [ABSTRACT FROM AUTHOR]

STUDY QUESTION How does haploinsufficiency of the paternal-effect gene Dnmt3L affect DNA methylation establishment and stability in the male germline? SUMMARY ANSWER Reduced expression of DNMT3L in male germ cells, associated with haploinsufficiency of the paternal-effect gene Dnmt3L, results in abnormal hypomethylation of prenatal germline progenitor cells. WHAT IS KNOWN ALREADY The DNA methyltransferase regulator Dnmt3-Like (Dnmt3L) is a paternal-effect gene required for DNA methylation acquisition in male germline stem cells and their precursors. In males, DNMT3L deficiency causes meiotic abnormalities and infertility. While Dnmt3L heterozygous males are fertile, they have abnormalities in X chromosome compaction and postmeiotic gene expression and sire offspring with sex chromosome aneuploidy. It has been proposed that the paternal effects of Dnmt3L haploinsufficiency are due to epigenetic defects in early male germ cells. DNA methylation is an essential epigenetic modification essential for normal germ cell development. Since patterns of DNA methylation across the genome are initially acquired in prenatal male germ cells, perturbations in methylation could contribute to the epigenetic basis of the paternal effects in Dnmt3L+/− males. STUDY DESIGN, SIZE, DURATION This is a cross-sectional study of DNA methylation in Dnmt3L+/+ versus Dnmt3L+/− male germ cells collected from mice at 16.5 days post-coitum (dpc), Day 6 and Day 70 (n = 3 per genotype, each n represents a pool of 2–20 animals). Additionally, DNA methylation was compared in enriched populations of spermatogonial stem cells (SSC)/progenitor cells from Dnmt3L+/+ and Dnmt3L+/− males following ∼2 months in culture. MATERIALS, SETTING, METHODS DNA methylation at intergenic loci along chromosomes 9 and X was examined by quantitative analysis of DNA methylation by real-time polymerase chain reaction at the time of initial acquisition of epigenetic patterns in the prenatal male germline (16.5 dpc) and compared with patterns in early post-natal spermatogonia (Day 6) and in spermatozoa in mice. DNA methylation status at CpG-rich sites across the genome was assessed in spermatogonial precursors from Day 4 male mice using restriction landmark genomic scanning. MAIN RESULTS AND THE ROLE OF CHANCE At 16.5 dpc, 42% of intergenic loci examined along chromosome 9 and 10% of those along chromosome X were hypomethylated in Dnmt3L heterozygotes. By Day 6 and in spermatozoa, germ cell DNA methylation was similar in heterozygous and wild-type mice. DNA methylation stability of acquired patterns in wild-type and Dnmt3L+/− SSC/progenitor cell culture was analyzed at numerous loci across the genome in cells cultured in vitro and collected at passages 6–28. While the methylation of most loci was stable in culture over time, differences at ∼1% of sites were found between Dnmt3L+/− and Dnmt3L+/+ cultures. LIMITATIONS, REASONS FOR CAUTION Evaluation of DNA methylation in SSCs can only be performed after a period of culture limiting the investigation to changes observed during culture when compared with DNA methylation differences between genotypes that could be present at the beginning of culture establishment. WIDER IMPLICATIONS OF THE FINDINGS The DNA methylation defects described here in prenatal male germline progenitor cells and SSC culture are the earliest epigenetic perturbations yet identified for a mammalian paternal-effect gene and may influence downstream epigenetic events in germ cells at later stages of development. Together, the results provide evidence of a ‘window’ of susceptibility in prenatal male germ cell precursors for the induction of epimutations due to genetic perturbations and, potentially, in utero environmental exposures. STUDY FUNDING/COMPETING INTEREST(S) Canadian ... [ABSTRACT FROM AUTHOR]

Inheritance of grape berry volatile compounds was studied in the half-sib populations of 'Jingxiu' × 'Muscat of Alexandria' and 'Jingxiu' × 'Xiangfei' during two successive years. Twenty-two volatile compounds were identified via GC-MS. Monoterpenes were detected in the paternal parents 'Muscat of Alexandria' and 'Xiangfei', which were Muscat grapes, but not in the non-Muscat maternal parent 'Jingxiu'. Four C6 compounds, five carbonyls and one ester (ethyl acetate) were found in all the parents, 2-ethylhexanol (alcohol) in 'Jingxiu' and 'Muscat of Alexandria', and hexyl acetate (ester) in 'Jingxiu'. The paternal effect varied with year, while the inheritance patterns of volatile compounds, except for ( Z)-linalool oxide, were stable between years and between populations. Four C6 compounds, five carbonyls, two esters and one alcohol were typical quantitative traits in both half-sib populations in 2 years. Most monoterpenes, including geraniol, α-terpineol and linalool, exhibited continuous variation in the half-sib progenies, but some other monoterpenes, such as ( Z)-rose oxide, nerol oxide, nerol, neral, geranial and geranic acid, appeared to segregate into presence or absence in the progenies (1:1). However, ( Z)-linalool oxide, behaved as a quantitative trait in the 'Jingxiu' × 'Muscat of Alexandria' population, but segregated into presence or absence (1:1) in the 'Jingxiu' × 'Xiangfei' population for both years. [ABSTRACT FROM AUTHOR]

The well documented increase in age that women conceive their first child has detracted from a similar change observed in males. As both males and females decide to conceive later, the question of whether this may impact their fertility individually and as a couple becomes even more crucial. A paternal age of over 40 years at the time of conception is a frequently quoted male age threshold, however, currently there is no clearly accepted definition of advanced paternal age or even a consensus on the implications of advancing male age. In this paper, we review some of the potential risks to the offspring of advancing male age and examine. The data available regarding pregnancy outcomes based on paternal age in both the fertile and infertile populations. Within the infertile population specifically, we examine the association between male age and outcomes based on treatment modality, including intrauterine insemination (IUI), in vitro fertilization (IVF), and donor oocyte IVF. Finally, we discuss the various mechanisms by which male age may impact sperm and fertility potential, including sperm DNA damage. [ABSTRACT FROM AUTHOR]

The neriid fly Telostylinus angusticollis is being developed as a model organism for experimental research on developmental plasticity, nongenetic inheritance, ageing and sexual selection. No genetic information is currently available for T. angusticollis, so to facilitate paternity analyses for experimentation we characterised 17 polymorphic microsatellites for this species based on MiSeq sequences. The loci had, on average, 4.1 alleles and the observed heterozygosity ranged from 0.250 to 0.889. We show that MiSeq can be used successfully to develop microsatellite markers. [ABSTRACT FROM AUTHOR]

This prospective randomized study investigated whether intracytoplasmic sperm injection (ICSI) outcome can be improved with sperm preselection under ×6000 magnification and intracytoplasmic morphologically selected sperm injection (IMSI) in patients with teratozoospermia and characterized embryo development and quality regarding sperm morphology and presence of head vacuoles. Couples with isolated teratozoospermia were divided into two groups: IMSI group (n = 52) and ICSI group (n = 70) and fertilization, blastocyst and clinical pregnancy rates were compared. Oocytes from 30 randomly chosen patients from the IMSI group were injected with spermatozoa that had been previously classified under ×6000 magnification into four classes according to the number and size of vacuoles in the head and then cultured separately. Pronuclear morphology, embryo development and blastomere viability were estimated to investigate the influence of sperm morphology, especially vacuoles, on embryo developmental capacity. A significantly higher clinical pregnancy rate was achieved in the IMSI group compared with the ICSI group (48% versus 24%, P < 0.05). Fertilization with spermatozoa without head vacuoles yielded higher number of morphologically normal zygotes, higher blastocyst rate and smaller proportion of arrested embryos than spermatozoa with vacuoles and other head defects. IMSI is a method of choice in patients with teratozoospermia. [ABSTRACT FROM AUTHOR]

Across many fish species, large females tend to exhibit higher individual reproductive success due to elevated fecundity and the provisioning of better conditioned eggs and offspring compared to small females. By contrast, effects of paternal body size on reproductive success are less well understood. We disentangled the maternal- and paternal-size dependent effects on reproductive output and early life history in zebrafish ( Danio rerio). In the laboratory, females and males from four size categories (small, medium-sized, large and very large) were allowed to spawn freely in a full factorial design with 10 replicates per size combination. As expected, larger females produced more eggs and better conditioned offspring compared to smaller females. Male body size further contributed to zebrafish reproductive success: offspring sired by large males exhibited higher hatching probability and these offspring also hatched earlier and larger than offspring fertilized by small males. However, the largest males experienced lower mating success and received fewer eggs than males of the smaller size classes. While male body size substantially affected reproductive success in zebrafish, it remained unclear whether and to what degree direct paternal effects (e.g., related to sperm quality) or indirect paternal effects stemming from differential allocation patterns by females were the mechanism behind our findings. Answering this question constitutes an important future research topic. [ABSTRACT FROM AUTHOR]

Abstract: Though there are multiple routes through which parents can influence their offspring, recent studies of environmentally induced epigenetic variation have highlighted the role of non-genomic pathways. In addition to the experience-dependent modification of DNA methylation that can be achieved via mother–infant interactions, there has been increasing interest in the epigenetic mechanisms through which paternal influences on offspring development can be achieved. Epidemiological and laboratory studies suggest that paternal nutritional and toxicological exposures as well as paternal age and phenotypic variation can lead to variations in offspring and, in some cases, grand-offspring development. These findings suggest a potential epigenetic germline inheritance of paternal effects. However, it may be important to consider the interplay between maternal and paternal influences as well as the experimental dissociation between experience-dependent and germline transmission when exploring the role of epigenetic variation within the germline as a mediator of these effects. In this review, we will explore these issues, with a particular focus on the potential role of paternally induced maternal investment, highlight the literature illustrating the transgenerational impact of paternal experiences, and discuss the evidence supporting the role of epigenetic mechanisms in maintaining paternal effects both within and across generations. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]

Recent evidence shows that seminal fluid can affect females and offspring independently of fertilisation in species lacking conventional ‘nuptial gifts’. We argue that a hypothesis from paternal investment systems – that selection can favour changing female preferences that maximise both sperm-borne and seminal fluid-borne benefits – could therefore apply much more broadly. [ABSTRACT FROM AUTHOR]

The ‘good genes’ hypothesis predicts that males advertise their quality with different sexual ornaments and that females are able to recognize the genetic quality of males by evaluating these characteristics. In the present study, we investigated the parental effects on offspring performance (feeding and swimming ability of newly-hatched larvae) and examined whether male ornamentation indicates offspring success in performance trials of whitefish ( Coregonus lavaretus Linnaeus). Offspring first-feeding success had a strong paternal effect and it was also positively correlated with the size of male breeding tubercles, indicating that breeding ornamentation of males can function as an honest indicator of their genetic quality. In addition, the observed positive correlation between male tubercle size and condition factor suggests that highly ornamented males are efficient foragers and that this trait may have a heritable basis. By contrast to feeding success, only a maternal effect was found in the swimming ability of the larvae. Clear family-specific differences observed in both measures of performance strongly suggest that parental identity may have important effects on larval survival in the wild. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98, 532–539. [ABSTRACT FROM AUTHOR]

Reciprocal differences have been observed widely for given traits in fish breeding programs, but maternal and paternal effects and heritable extranuclear genetic effects have often been omitted in the evaluation of genetic variance. In this study, we have applied a mixed genetic model to conduct a complete diallel cross using three varieties of red common carp ( Cyprinus carpio L.), namely, C. carpio. var. singuonensis, C. carpio var. wuyuanensis and C. carpio var. color. Parental and direct (additive and dominance) genetic effects for growth-related traits at 8 and 20 months post-hatch were analyzed. At 8 months post-hatch, only significant additive and dominance variances were observed, while maternal and paternal variances were low and non-significant in the traits evaluated: body weight, total length, standard length, pre-dorsal height, pre-dorsal width, caudal peduncle length, and caudal peduncle height. At 20 months post-hatch, with the exception of significant additive and/or dominance variances, maternal variances were significant for the traits of body weight, pre-dorsal height, pre-dorsal width, and caudal peduncle height, and the paternal variance was significant only for total length. The maternal effects in the common carp had greater genetic influence on offspring than the paternal effects. Female C. carpio var. wuyuanensis were more suitable as brooders than males, but both female and male C. carpio var. color can be used as brooders according to breeding programs of improved traits. Cyprinus carpio var. singuonensis was the worst brooder of the three varieties of common carp evaluated. [ABSTRACT FROM AUTHOR]

Objective: To evaluate objectively whether poor sperm quality affects sequential events from fertilization to delivery in fresh intracytoplasmic sperm injection (ICSI) and subsequent frozen–thawed embryo transfer (ET) cycles. Design: Retrospective study. Setting: University-based centers for reproductive medicine. Patient(s): For unbiased comparison, 206 cycles were chosen from 1,999 cycles of patients who underwent ICSI-ET and/or subsequent frozen–thawed ET. Cycles met the following criteria: day 3 ET; female age, <40 y; number of retrieved oocytes, ≥5; no split insemination; and no female factors but tubal factor. Intervention(s): None. Main Outcome Measure(s): The rates of fertilization, embryo implantation, clinical pregnancy, and delivery and sequential embryonic score (SES) were compared between normal-spermatogenesis patients (NSPs) and defective-spermatogenesis patients (DSPs). Result(s): Although sum SES, mean SES, and top SES of transferred embryos on day 3 were similar between NSPs and DSPs, the rates of implantation, clinical pregnancy, and delivery of NSPs were significantly higher than those of DSPs. Furthermore, subsequent ET cycles with frozen–thawed embryos in NSPs and DSPs who failed to achieve pregnancy in their fresh cycles showed that rates of implantation and clinical pregnancy also were significantly lower in DSPs. Conclusion(s): Quality of sperm may influence embryo implantation and subsequent pregnancy outcomes without impairment of embryo quality. [Copyright &y& Elsevier]

We used a crossing experiment to investigate post-zygotic barriers that might limit introgression between a pair of closely-related, gynodioecious plant species – the widespread weed Silene vulgaris and the local Swedish endemic S. uniflora ssp. petraea. The study not only considered the effects of hybridization on conventionally-used (primary) fitness components such as seed set and progeny survival, but also provided a test for the effects of interspecific hybridization on characters with more subtle or habitat-specific effects on fitness. We detected highly significant paternal effects on seed germination properties, with the germination characteristics of hybrid seed resembling those of the species that served as the pollen donor. These paternal effects on germination represent a potentially strong barrier to interspecific introgression in the two species’ natural habitats, where an inappropriate germination response in the habitat of the maternal parent may lead to the failure of seedling establishment. Interspecific crosses had weak or variable effects on progeny survival, flowering and sex ratio, but these effects could not be interpreted in terms of barriers to introgression. Our results indicate that nuclear restorers in S. vulgaris have the capacity to suppress cytoplasmic male-sterility genes in its endemic congener. [ABSTRACT FROM AUTHOR]

Campylobacter jejuni is one of the most common causes of acute enteritis worldwide. Chickens are believed to be the main reservoir of C. jejuni. The role that host genetics play in resistance/susceptibility to C. jejuni colonization in broilers is still not clear. Day-old broilers from 2 parental lines (A and B) and their F1 reciprocal crosses (C and D) were challenged orally with 105 cfu of C. jejuni to address the role of genetics in determining resistance/susceptibility to C. jejuni colonization in broilers. Cloacal swabs were collected on 6, 10, and 13 d postinoculation (dpi), and cecal contents cultured for C. jejuni on 7 and 14 dpi. The number of C. jejuni colonies in the cloacal swabs and cecal contents of each bird were recorded at each time point. Significantly fewer bacteria were found in the cecal contents from line A than B (P < 0.05) and cross D (A♀ × B♂) when compared with cross C (A♂ × B♀) at both 7 and 14 dpi. There was a significant correlation between C. jejuni counts in cloacal swabs and those in cecal contents. The results indicated that a paternal effect might be one of the important genetic factors influencing resistance to C. jejuni colonization in broilers. [ABSTRACT FROM AUTHOR]

Previous studies have shown that repeated intracytoplasmic sperm injection (ICSI) failures can be caused by a paternal effect. Other studies have suggested that ICSI results are compromised if morphologically abnormal spermatozoa are injected into oocytes. This study was undertaken to evaluate the usefulness of a high-magnification optical system to select spermatozoa to be used for ICSI (high-magnification ICSI) in couples with repeated conventional ICSI failures. Couples with two or more previous conventional ICSI failures underwent an additional conventional ICSI attempt, followed by a high-magnification ICSI attempt. The outcomes of the two sequential attempts were compared. In 72 of these patients, sperm DNA integrity was assessed. In the whole group of 125 couples with repeated ICSI failures, high- magnification ICSI improved clinical outcomes (pregnancy, implantation, delivery and birth rates) without affecting biological outcomes (fertilization and cleavage rates, embryo morphology), The improvement of clinical ICSI outcomes was evident both in patients with an elevated degree of sperm DNA fragmentation and in those with normal sperm DNA status. It is concluded that high-magnification ICSI improves clinical outcomes in couples with previous repeated conventional ICSI failures. [ABSTRACT FROM AUTHOR]

Cell divisions in the human preimplantation embryo can be compromised by deficiencies in sperm nuclear genome or sperm-derived developmentally relevant cytoplasmic factors, oocyte activating substance and centriole. Sperm nuclear deficiencies are usually of detected before the 8-cell stage of embryo development, when a major expression of sperm-derived genes has begun. Sperm cytoplasmic deficiencies can be detected as early as the 1-cell zygote and then throughout the preimplantation development. The terms 'late paternal effect' and 'early paternal effect' have been suggested to denote these two pathological conditions. The late paternal effect is associated with an increased incidence of sperm DNA fragmentation. No association with sperm DNA damage has been found for the early paternal effect. The diagnosis of the late paternal effect is thus based on the examination of sperm DNA integrity, which should be performed in cases of repeated assisted reproduction failure even if morphologically normal embryos result from fertilization with the patient's spermatozoa. The only element leading to the diagnosis of the early paternal effect is poor zygote and embryo morphology and low cleavage speed. The absence of increased sperm DNA damage does not exclude the presence of this pathology, ICSI with testicular spermatozoa has recently been shown to be an efficient treatment for the late paternal effect. The use of oral antioxidant treatment in this indication has also given promising results. [ABSTRACT FROM AUTHOR]

BACKGROUND: It is known that repeated failure of assisted reproduction treatment (ART) can be due to a paternal effect. This study was undertaken to analyse the possible relationship between ART failure and sperm DNA fragmentation. METHODS: Zygote morphology and the percentage of spermatozoa with fragmented DNA (assessed by TUNEL) were compared in two groups using donor oocytes for ICSI attempts. The experimental group consisted of 18 infertile couples who had each undergone three previous failed ART attempts. The control group included 18 randomly selected infertile couples undergoing their first ICSI attempt. Both groups used sibling oocytes from the same donors. RESULTS: In 10 couples of the experimental group, the adverse paternal effect was evident as early as the zygote stage. This early paternal effect was not associated with sperm DNA fragmentation. In eight couples of the experimental group, the adverse paternal effect did not produce any perceptible deterioration of zygote morphology. However, this late paternal effect was associated with an increased percentage of spermatozoa with fragmented DNA. CONCLUSIONS: Early paternal effect can compromise ART outcomes in the absence of increased sperm DNA fragmentation. Evaluation of sperm DNA integrity is useful to detect late paternal effect, which is not associated with morphological abnormalities at the zygote and early cleavage stages. [ABSTRACT FROM AUTHOR]

Transgenerational epigenetic inheritance (TEI) requires transmission of environmentally induced epigenetic changes and associated phenotypes to subsequent generations without continued exposure to the environmental factor that originated the change. TEI is well-established in plants and Caenorhabditis elegans ; however, occurrence in mammals is debated and poorly understood. Here, we examined whether paternal diet from weaning to puberty-induced changes in sperm DNA methylation that were transmitted to subsequent generations. Over 100 methylated cytosines, environmentally altered in the F0 generation, were inherited by the F1 and F2 generations. Furthermore, the F0 paternal diet was associated with growth and male fertility phenotypes in subsequent generations. Differentially methylated cytosines were correlated with gene expression. Our results demonstrate that some sperm methylation sites may escape DNA methylation erasure and are transmitted to subsequent generations despite the 2 waves of epigenetic programming: in primordial germ cells and in embryos after fertilization. These results advance our understanding of the complex relationships between nature and nurture., (© The Author(s) 2022. Published by Oxford University Press on behalf of the National Academy of Sciences.)

In addition to the well-established DNA-based inheritance, phenotypes can also be transmitted across generations without changes in the DNA sequence, a process referred to as epigenetic inheritance. Environmental exposures can alter epigenetic marks, including DNA methylation, in sperm and oocytes. These epigenetic changes can be inherited at fertilization and thus potentially affect both fetal programming and phenotypic outcomes of the offspring. The transmission of epigenetic marks across two generations is termed intergenerational epigenetic inheritance, and the transmission of these marks across multiple generations is called transgenerational epigenetic inheritance. Transgenerational epigenetic inheritance is well-established in plants, Caenorhabditis elegans , and fruit flies, but its occurrence in mammals is controversial. In this review, I provide examples of mechanisms of epigenetic inheritance and discuss points of contention. Also, I examine the effects of maternal and paternal environmental exposures on the phenotypes of the offspring and whether these effects are intergenerational or transgenerational. Lastly, I discuss the gaps of knowledge in this research area that needs to be addressed in future studies. • Transgenerational epigenetic inheritance is well-established in plants, Caenorhabditis elegans , and fruit flies • At present, there is no definitive evidence of transgenerational epigenetic inheritance in farm animals • Most epigenetic inheritance studies have been focused on the maternal environmental effects on the subsequent generation • Future studies in farm animals should investigate the type of epigenetic markers that can be altered in response to environmental insults and the extent of inheritance of those marks across generations [ABSTRACT FROM AUTHOR]

The natural host of Ophraella notulata is Iva frutescens (Asteraceae); its close relative feeds on a related plant, Ambrosia artemisiifolia. We reared beetles on both plants, obtained progeny from the four possible crosses (two sexes X two parental hosts), and reared the progeny on both plant species. Survival to the imaginal stage of progeny reared on Iva varied with both maternal and paternal host. Hatchling feeding response to both plants showed a maternal host X paternal host interaction. Consumption of Ambrosia by adult beetles was, counter to expectation, higher for progeny of Iva-reared males than Ambrosia-reared males. Oviposition response, although based on too few data to be definitive, was peculiar: parental host did not affect oviposition on Ambrosia; on Iva daughters of Iva-reared males laid significantly more eggs than did daughters of Ambrosia-reared males, but only if they had been reared on Iva; those reared on Ambrosia displayed the reverse pattern. We discuss the possibility that nongenetic paternal transmission of host plant effects may explain these results, but offer a somewhat uncomfortable hypothesis of selection as a preferable explanation. An important outcome of the experiment is that it provided no evidence of maternal effects of host plant on offspring feeding or oviposition. [ABSTRACT FROM AUTHOR]

Recent studies suggest that stress can lead to variations in offspring development. However, whether paternal systemic inflammation induces phenotypic changes in the offspring remains unclear. Here, we established an in vivo mouse model of systemic inflammation and investigated the long-term consequences on the offspring. Male, but not female offspring derived from inflammatory fathers (LPS-F1) grew faster than those derived from the control fathers (CON–F1). Moreover, the LPS-F1 males had higher capacity for liver regeneration after injury, as indicated by decreased hepatic fibrosis, apoptosis, and increased hepatocyte proliferation upon carbon tetrachloride challenge. Insulin-like growth factor 2 (Igf2), a key mitogen that drives growth and liver regeneration, was significantly upregulated in the livers of male, but not female offspring from fathers with inflammation. Taken together, paternal inflammation alters the hepatic Igf2 expression and reprograms growth and liver regeneration in male but not female offspring. • Paternal inflammation reprogrammed growth performance in male offspring. • Paternal inflammation promoted liver regeneration in male offspring after injury. • Paternal inflammation upregulated Igf2 levels in liver and serum of male offspring. [ABSTRACT FROM AUTHOR]

Predation threat impacts prey behavior, physiology, and fitness. Stress-mediated alterations to the paternal epigenome can be transmitted to offspring via the germline, conferring a potential advantage to offspring in predator-rich environments. While intergenerational epigenetic transmission of paternal experience has been demonstrated in mammals, how paternal predator exposure might alter offspring phenotypes across development is unstudied. We exposed male mice to a predator odor (2,4,5-trimethylthiazoline, TMT) or a neutral odor (banana extract) prior to mating and measured offspring behavioral phenotypes throughout development, together with adult stress reactivity and candidate gene expression in the prefrontal cortex, hippocampus, amygdala, and hypothalamus. We predicted that offspring of TMT-exposed males would be less active, would display elevated anxiety-like behaviors, and would have a more efficient stress response relative to controls, phenotypes that should enhance predator avoidance in a high predation risk environment. Unexpectedly, we found that offspring of TMT-exposed males are more active, exhibit less anxiety-like behavior, and have decreased baseline plasma corticosterone relative to controls. Effects of paternal treatment on neural gene expression were limited to the prefrontal cortex, with increased mineralocorticoid receptor expression and a trend towards increased Bdnf expression in offspring of TMT-exposed males. These results suggest that fathers exposed to predation threat produce offspring that are buffered against non-acute stressors and, potentially, better adapted to a predator-dense environment because they avoid trade-offs between predator avoidance and foraging and reproduction. This study provides evidence that ecologically relevant paternal experience can be transmitted through the germline, and can impact offspring phenotypes throughout development. • Anxiety-like behavior is reduced in experimental offspring of predator-stressed males. • Baseline corticosterone is reduced in experimental offspring. • Mineralocorticoid receptor expression is higher in experimental offspring brains. • Developmental shifts in anxiety-like behavior differ by sex in experimental offspring. • Paternal predation risk exposure buffers offspring response to non-acute stress. [ABSTRACT FROM AUTHOR]

We present an important characteristic of trio models which may lead to bias and loss of power when one parent is unmodeled in trio analyses. Motivated by recent interest in estimating parental effects on postnatal and later-life phenotypes, we consider a causal model where each parent has both an effect on their child's phenotype which is mediated through the genotype transmitted to the child and a direct effect on the phenotype through the parentally provided environment. We derive the power and bias of models in which one parent's genotype is not modeled, showing that while the effect of the child's genotype is biased in the direction of the unmodeled parent's effect as expected, the estimated effect of the observed parent's genotype is also biased in the opposite direction. While this phenomenon may not be intuitive under the assumption of random mating, it can be explained by intermediate confounding of the child's genotype-phenotype effect. These observations have implications for the accurate estimation of maternal and paternal effects in trio data sets with missing genotype data., (© 2020 Wiley Periodicals, Inc.)

The sperm pre-fertilization environment has recently been suggested to mediate remarkable transgenerational consequences for offspring phenotype (transgenerational plasticity, TGB), but the adaptive significance of the process has remained unclear. Here, we studied the transgenerational effects of sperm pre-fertilization thermal environment in a cold-adapted salmonid, the European whitefish ( Coregonus lavaretus ). We used a full-factorial breeding design where the eggs of five females were fertilized with the milt of 10 males that had been pre-incubated at two different temperatures (3.5°C and 6.5°C) for 15 h prior to fertilization. Thermal manipulation did not affect sperm motility, cell size, fertilization success or embryo mortality. However, offspring that were fertilized with 6.5°C-exposed milt were smaller and had poorer swimming performance than their full-siblings that had been fertilized with the 3.5°C-exposed milt. Furthermore, the effect of milt treatment on embryo mortality varied among different females (treatment×female interaction) and male-female combinations (treatment×female×male interaction). Together, these results indicate that sperm pre-fertilization thermal environment shapes offspring phenotype and post-hatching performance and modifies both the magnitude of female (dam) effects and the compatibility of the gametes. Generally, our results suggest that short-term changes in sperm thermal conditions may have negative impact for offspring fitness. Thus, sperm thermal environment may have an important role in determining the adaptation potential of organisms to climate change. Detailed mechanism(s) behind our findings require further attention., Competing Interests: Competing interestsThe authors declare no competing or financial interests., (© 2018. Published by The Company of Biologists Ltd.)

Telomere-capping complexes (TCCs) protect the ends of linear chromosomes from illegitimate repair and end-to-end fusions and are required for genome stability. The identity and assembly of TCC components have been extensively studied, but whether TCCs require active maintenance in nondividing cells remains an open question. Here we show that Drosophila melanogaster requires Deadbeat (Ddbt), a sperm nuclear basic protein (SNBP) that is recruited to the telomere by the TCC and is required for TCC maintenance during genome-wide chromatin remodeling, which transforms spermatids to mature sperm. Ddbt-deficient males produce sperm lacking TCCs. Their offspring delay the initiation of anaphase as early as cycle 1 but progress through the first two cycles. Persistence of uncapped paternal chromosomes induces arrest at or around cycle 3. This early arrest can be rescued by selective elimination of paternal chromosomes and production of gynogenetic haploid or haploid mosaics. Progression past cycle 3 can also occur if embryos have reduced levels of the maternally provided checkpoint kinase Chk2. The findings provide insights into how telomere integrity affects the regulation of the earliest embryonic cell cycles. They also suggest that other SNBPs, including those in humans, may have analogous roles and manifest as paternal effects on embryo quality., (Copyright © 2016 by the Genetics Society of America.)

Forward genetics remains an important approach for the unbiased identification of factors involved in biological pathways. Forward genetic analysis in the zebrafish has until now largely been restricted to the developmental period from zygotic genome activation through the end of embryogenesis. However, the use of the zebrafish as a model system for the analysis of late larval, juvenile and adult traits, including fertility and maternal and paternal effects, continues to gain momentum. Here, we describe two approaches, based on an F3-extended family and gynogenetic methods, that allow genetic screening for, and recovery of mutations affecting post-embryonic stages, including adult traits, fertility, and parental effects. For each approach, we also describe strategies to maintain, map, and molecularly clone the identified mutations., (Copyright © 2016 Elsevier Inc. All rights reserved.)