Transgenerational Transfer Research Articles

Corticosterone Levels during the Nesting Process in Red-eared Sliders (Trachemys scripta)

Abstract Free-living vertebrates tend to respond to environmental challenges by increasing circulating glucocorticoid levels. Changes in glucocorticoids can modulate various aspects of physiology and behavior, which can have fitness benefits in the short term but may be detrimental to fitness if elevated levels are frequent, prolonged, or both. The transfer of glucocorticoids from females to offspring might also have fitness consequences, but there is less known about the potential effects of transgenerational glucocorticoid transfer. Our study examined corticosterone levels in female Red-eared Sliders (Trachemys scripta) during the nesting season because of the potential fitness consequences for both females and offspring. Whether caught in aquatic traps or caught during the nesting process, females had similar circulating corticosterone levels that were relatively low. However, when females were subjected to a restraint protocol, corticosterone rose. Therefore, corticosterone levels may be elevated duri...

Long antibody persistence and transgenerational transfer of immunity in a long-lived vertebrate.

Although little studied in natural populations, the persistence of immunoglobulins may dramatically affect the dynamics of immunity and the ecology and evolution of host-pathogen interactions involving vertebrate hosts. By means of a multiple-year vaccination design against Newcastle disease virus, we experimentally addressed whether levels of specific antibodies can persist over several years in females of a long-lived procellariiform seabird-Cory's shearwater-and whether maternal antibodies against that antigen could persist over a long period in offspring several years after the mother was exposed. We found that a single vaccination led to high levels of antibodies for several years and that the females transmitted antibodies to their offspring that persisted for several weeks after hatching even 5 years after a single vaccination. The temporal persistence of maternally transferred antibodies in nestlings was highly dependent on the level at hatching. A second vaccination boosted efficiently the level of antibodies in females and thus their transfer to offspring. Overall, these results stress the need to consider the temporal dynamics of immune responses if we are to understand the evolutionary ecology of host-parasite interactions and trade-offs between immunity and other life-history characteristics, in particular in long-lived species. They also have strong implications for conservation when vaccination may be used in natural populations facing disease threats.

Hypoxia and environmental epigenetics.

Epigenetics refers to long-term modifications of gene activity that can be inherited, either somatically or transgenerationally, but that are independent of alterations in the primary base sequence of the organism's DNA. These changes can include chemical modifications of both the DNA bases and the proteins that associate with the DNA helices to form chromatin, the nucleic acid:protein complex of which the chromosomes are comprised. Epigenetic modifications can affect the accessibility of the DNA for transcription factors (the DNA-binding proteins that specify which genes are to be active or silent by modulating the recruitment of the transcriptional machinery that reads the information encoded in the sequence) and thereby regulate the expression of genes and alter the phenotype of the organism. Epigenetic marks can also be re-established following mitosis, allowing patterns of differential gene expression to be transmitted from one cell generation to the next, and can even be maintained through meiosis, allowing transgenerational transfer of regulatory cues. Unlike the information encoded in the DNA sequence, which is invariant between most cell types and over time, epigenetic information is tissue specific and can change in response to exogenous and endogenous perturbations. This responsive capacity enables a sensitive and reactive system that can optimize gene expression in relevant tissue in response to environmental change. The realization that organisms are capable of genetically 'reprograming' themselves as well as 'preprograming' future cells, and even future offspring to optimize gene expression for a given environment may have tremendous ramifications on our understanding of both acclimatization and adaptation to hypoxia.

Transgenerational transmission of the Glossina pallidipes hytrosavirus depends on the presence of a functional symbiome.

The vertically transmitted endosymbionts (Sodalis glossinidius and Wigglesworthia glossinidia) of the tsetse fly (Diptera: Glossinidae) are known to supplement dietary deficiencies and modulate the reproductive fitness and the defense system of the fly. Some tsetse fly species are also infected with the bacterium, Wolbachia and with the Glossina hytrosavirus (GpSGHV). Laboratory-bred G. pallidipes exhibit chronic asymptomatic and acute symptomatic GpSGHV infection, with the former being the most common in these colonies. However, under as yet undefined conditions, the asymptomatic state can convert to the symptomatic state, leading to detectable salivary gland hypertrophy (SGH+) syndrome. In this study, we investigated the interplay between the bacterial symbiome and GpSGHV during development of G. pallidipes by knocking down the symbionts with antibiotic. Intrahaemocoelic injection of GpSGHV led to high virus titre (109 virus copies), but was not accompanied by either the onset of detectable SGH+, or release of detectable virus particles into the blood meals during feeding events. When the F1 generations of GpSGHV-challenged mothers were dissected within 24 h post-eclosion, SGH+ was observed to increase from 4.5% in the first larviposition cycle to >95% in the fourth cycle. Despite being sterile, these F1 SGH+ progeny mated readily. Removal of the tsetse symbiome, however, suppressed transgenerational transfer of the virus via milk secretions and blocked the ability of GpSGHV to infect salivary glands of the F1 progeny. Whereas GpSGHV infects and replicates in salivary glands of developing pupa, the virus is unable to induce SGH+ within fully differentiated adult salivary glands. The F1 SGH+ adults are responsible for the GpSGHV-induced colony collapse in tsetse factories. Our data suggest that GpSGHV has co-evolved with the tsetse symbiome and that the symbionts play key roles in the virus transmission from mother to progeny.

Religious-Related Abuse in the Family

Religion provides directives for positive moral action and the promotion of human welfare; but religious beliefs can also foster and justify abusive behavior in the context of family life and child rearing. Parents, who are emotionally distraught and cannot control their responses to their child’s needs or misbehavior, might wield religious ideas to intimidate and control their children. In our paper we set forth two fundamental types of religion-related emotional abuse and discuss the complex role that religion can play in perpetuating abusive family relationships. We address the emotional aspects of religion-related abuse and also its transgenerational transfer. We present a case illustration focusing on how such abuse leads to dysfunctional patterns of behavior in family relationships and disruptions in emotion regulation processes. Applying a Relational Family Therapy model, we consider select therapeutic implications for addressing and overcoming religious abuse and restoring functional emotion regulation processes in families.

COEVOLUTION BETWEEN MATERNAL TRANSFER OF IMMUNITY AND OTHER RESISTANCE STRATEGIES AGAINST PATHOGENS

Among the wide variety of resistance mechanisms to parasitism, the transgenerational transfer of immunity from mother to offspring has largely been overlooked and never included in evolutionary or coevolutionary studies of resistance mechanisms. Here we study the evolution and coevolution of various resistance mechanisms with a special focus on maternal transfer of immunity. In particular we show that maternal transfer of immunity is only expected to evolve when cross immunity is high and when the pathogens have an intermediate virulence. We also show that the outcome of the coevolution between various resistance mechanisms depends critically on the life span of the host. We predict that short-lived species should invest in avoidance strategies, whereas long-lived species should invest in acquired resistance mechanisms. These results may help understanding the diversity of resistance strategies that have evolved in vertebrate species. Our framework also provides a general basis for the study of the evolution of other transgenerational resistance mechanisms.

Memory and Identity in South Africa: Contradictions and Ambiguities in the Process of Post-apartheid Memorialization

The article explores commemorative markers as containers of intangible heritage in post-apartheid South Africa, with special reference to the case study of the Duncan Village Massacre memorial that was unveiled in 2008 in the Buffalo City Municipality (Eastern Cape) in memory of the victims of the so-called Duncan Village Massacre of August 1985. This event is an example of many similar cases of apartheid-era township violence, where state security forces shot and killed members of a protesting community crowd; and the memorial is an example of many similar commemorative markers that have been installed under the aegis of the national post-apartheid government since 1994. After considering the historical background of the Duncan Village Massacre and the significance of the way in which it is now being commemorated, the article traces the process of the memorial's production, installation and public reception, considering in particular the issue of community consultation and the role of heritage in development. It is argued that the memorial is not only a symbol of anti-apartheid resistance, as intended, but also a symbol of the contradictions that characterize the post-apartheid nation; which raises serious questions about the preservation of cultural heritage and the trans-generational transfer of memory and oral history in a specific African context.

Parental hypoxic exposure confers offspring hypoxia resistance in zebrafish (Danio rerio)

Parental influences are a potentially important component of transgenerational transfer of phenotype in vertebrates. This study examined how chronic hypoxic exposure on adult zebrafish (Danio rerio) affected the phenotype of their offspring. Separate adult populations were exposed to hypoxia (13.1 kPa O(2)) or normoxia (21.1 kPa O(2)) for periods ranging from 1 to 12 weeks. Adults were then returned to normoxia and bred within experimental groups. Adult fecundity and egg characteristics (volume of egg, yolk and perivitelline fluid) were assessed. Subsequently, larval body length, time to loss of equilibrium in severe hypoxia (~4 kPa O(2)), and critical thermal minima (CT(min)) and maxima (CT(max)) were measured at 6, 9, 12, 15, 18, 21 and 60 days post-fertilization (d.p.f.). Adult fecundity was depressed by hypoxic exposure. Egg component volumes were also depressed in adults exposed to 1-2 weeks of hypoxia, but returned to control levels following longer hypoxic exposure. Adult hypoxic exposures of >1 week resulted in longer body lengths in their larval offspring. Time to loss of equilibrium in severe hypoxia (i.e. hypoxic resistance) in control larvae decreased from 6 to 12 d.p.f., remaining constant thereafter. Notably, hypoxic resistance from 6 to 18 d.p.f. was ~15% lower in larvae whose parents were exposed to just 1 week of chronic hypoxia, but resistance was significantly increased by ~24-30% in 6-18 d.p.f. larvae from adults exposed to 2, 3 or 4 weeks of hypoxia. CT(min) (~10-12°C) and CT(max) (~39.5°C) were unchanged by parental hypoxic exposure. This study demonstrates that parental hypoxic exposure in adult zebrafish has profound epigenetic effects on the morphological and physiological phenotype of their offspring.

Psychic Impact and Outcome of the Chinese Cultural Revolution (1966–1976). A Psychoanalytic Research Project at the Sigmund‐Freud‐Institut, Frankfurt (Germany)1

ABSTRACTThe paper lines out a research project done as a cooperation between Sigmund‐Freud‐Institut (Frankfurt, Germany) and 5 Chinese professors of different universities. It focusses at traumatic experiences of witnesses of the Chinese Cultural Revolution and the transgenerational transfer to one of their children. Method and results of this qualitative research are outlined. Copyright © 2011 John Wiley & Sons, Ltd.

P01-314 - Transgenerational transfer of family secret - case presentation

ObjectiveWe wanted to show how the family secret of adoption can influence even second generation of members.Case studyGirl 15 years of age, high school first grade lived in complete family with older brother and younger sister. Father was a rigid structure, difficult in communication with other family members except youngest daughter. For a first check up she had come with her mother (previously psychiatry treated of depression). Girl was very depressed (CDI 24), her appearance expressed hopelessness, repeatedly thought about suicide, did not accomplish anything she wanted, to study for nurse, or an actress. Two years ago looking through some papers, she had find out that her mother was adopted as a baby, that changed her all life, relationship toward grandparents, could not study, focus on anything else. Just a few days ago she admitted to her mother that she knows a secret about her origins. Her mother also find out that she was adopted when she was 14 (the same age when her daughter find it out), some girls in the school told that to her. Finding out the truth was very devastating for her too.ConclusionTrans - generational transfer of family secret came to resonance of unconscious and girl find out the truth almost in the same age as mother. It has had stressful effect, but also influence trust, and cause anger and feeling of exclusion. Silence has aggressive except protective function. Adolescence as vulnerable developmental age made this girl more sensitive for this.

Egg yolk environment differentially influences physiological and morphological development of broiler and layer chicken embryos

Maternal effects are important in epigenetic determination of offspring phenotypes during all life stages. In the chicken (Gallus gallus domesticus), transgenerational transfer of egg yolk factors may set the stage for morphological and physiological phenotypic differences observed among breeds. To investigate the effect of breed-specific yolk composition on embryonic broiler and layer chicken phenotypes, we employed an ex ovo, xenobiotic technique that allowed the transfer of broiler and layer chicken embryos from their natural yolks to novel yolk environments. Embryonic day two broiler embryos developing on broiler yolk culture medium (YCM) had significantly higher heart rates than layer embryos developing on layer YCM (176±7 beats min(-1) and 147±7 beats min(-1), respectively). Broiler embryos developing on layer YCM exhibited heart rates typical of layer embryos developing normally on layer YCM. However, layer embryo heart rates were not affected by development on broiler YCM. Unlike O(2) consumption, development rate and body mass of embryos were significantly affected by exposure to different yolk types, with both broiler and layer embryos displaying traits that reflected yolk source rather than embryo genotype. Analysis of hormone concentrations of broiler and layer egg yolks revealed that testosterone concentrations were higher in broiler yolk (4.63±2.02 pg mg(-1) vs 3.32±1.92 pg mg(-1)), whereas triiodothyronine concentrations were higher in layer yolk (1.05±0.18 pg mg(-1) vs 0.46±0.22 pg mg(-1)). Thus, a complex synergistic effect of breed-specific genotype and yolk environment exists early in chicken development, with yolk thyroid hormone and yolk testosterone as potential mediators of the physiological and morphological effects.

Transgenerational transfer of ADHD-like phenotypes in prenatally ethanol-exposed Sprague–Dawley rat offsprings

International Journal of Developmental NeuroscienceVolume 28, Issue 8 p. 675-675 Article [P1.60]: Transgenerational transfer of ADHD-like phenotypes in prenatally ethanol-exposed Sprague–Dawley rat offsprings P. Kim, Corresponding Author P. Kim n/[email protected] Konkuk University, Republic of KoreaSearch for more papers by this authorI. Choi, I. Choi Konkuk University, Republic of KoreaSearch for more papers by this authorM.K. Kim, M.K. Kim Konkuk University, Republic of KoreaSearch for more papers by this authorJ.H. Ryu, J.H. Ryu Kyung Hee University, Republic of KoreaSearch for more papers by this authorC.Y. Shin, C.Y. Shin Konkuk University, Republic of KoreaSearch for more papers by this author P. Kim, Corresponding Author P. Kim n/[email protected] Konkuk University, Republic of KoreaSearch for more papers by this authorI. Choi, I. Choi Konkuk University, Republic of KoreaSearch for more papers by this authorM.K. Kim, M.K. Kim Konkuk University, Republic of KoreaSearch for more papers by this authorJ.H. Ryu, J.H. Ryu Kyung Hee University, Republic of KoreaSearch for more papers by this authorC.Y. Shin, C.Y. Shin Konkuk University, Republic of KoreaSearch for more papers by this author First published: 01 November 2010 https://doi.org/10.1016/j.ijdevneu.2010.07.100Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article. Volume28, Issue8Abstracts to the 18th Biennial Meeting of the International Society for Developmental Neuroscience, 6‐9 June 2010, Estoril, PortugalDecember 2010Pages 675-675 RelatedInformation

Intracellular uptake and associated toxicity of silver nanoparticles in Caenorhabditis elegans

Silver nanoparticles (AgNPs) are frequently used as antimicrobials. While the mechanism(s) by which AgNPs are toxic are unclear, their increasing use raises the concern that release into the environment could lead to environmental toxicity. We characterized the physicochemical behavior, uptake, toxicity (growth inhibition), and mechanism of toxicity of three AgNPs with different sizes and polyvinylpyrrolidone (PVP) or citrate coatings to the nematode Caenorhabditis elegans. We used wild-type (N2) C. elegans and strains expected to be sensitive to oxidative stress ( nth-1, sod-2 and mev-1), genotoxins ( xpa-1 and nth-1), and metals ( mtl-2). Using traditional and novel analytical methods, we observed significant aggregation and extra-organismal dissolution of silver, organismal uptake and, in one case, transgenerational transfer of AgNPs. We also observed growth inhibition by all tested AgNPs at concentrations in the low mg/L levels. A metallothionein-deficient ( mtl-2) strain was the only mutant tested that exhibited consistently greater AgNP sensitivity than wild-type. Although all tested AgNPs were internalized (passed cell membranes) in C. elegans, at least part of the toxicity observed was mediated by ionic silver. Finally, we describe a modified growth assay that permits differentiation between direct growth-inhibitory effects and indirect inhibition mediated by toxicity to the food source.

Epigenetics and transgenerational transfer: a physiological perspective

Epigenetics, the transgenerational transfer of phenotypic characters without modification of gene sequence, is a burgeoning area of study in many disciplines of biology. However, the potential impact of this phenomenon on the physiology of animals is not yet broadly appreciated, in part because the phenomenon of epigenetics is not typically part of the design of physiological investigations. Still enigmatic and somewhat ill defined is the relationship between the overarching concept of epigenetics and interesting transgenerational phenomena (e.g. 'maternal/parental effects') that alter the physiological phenotype of subsequent generations. The lingering effect on subsequent generations of an initial environmental disturbance in parent animals can be profound, with genes continuing to be variously silenced or expressed without an associated change in gene sequence for many generations. Known epigenetic mechanisms involved in this phenomenon include chromatin remodeling (DNA methylation and histone modification), RNA-mediated modifications (non-coding RNA and microRNA), as well as other less well studied mechanisms such as self-sustaining loops and structural inheritance. In this review we: (1) discuss how the concepts of epigenetics and maternal effects both overlap with, and are distinct from, each other; (2) analyze examples of existing animal physiological studies based on these concepts; and (3) offer a construct by which to integrate these concepts into the design of future investigations in animal physiology.

Evidence of an interannual effect of maternal immunization on the immune response of juveniles in a long‐lived colonial bird

Little is known about the maternal transfer of antibodies in natural host-parasite systems despite its possible evolutionary and ecological implications. In domestic animals, the maternal transfer of antibodies can enhance offspring survival via a temporary protection against parasites, but it can also interfere with the juvenile immune response to antigens. We tested the functional role of maternal antibodies in a natural population of a long-lived colonial seabird, the kittiwake (Rissa tridactyla), using a vaccine (Newcastle disease virus vaccine) to mimic parasite exposure combined with a cross-fostering design. We first investigated the role of prior maternal exposure on the interannual transmission of Ab to juveniles. We then tested the effect of these antibodies on the juvenile immune response to the same antigen. The results show that specific maternal antibodies were transferred to chicks 1 year after maternal exposure and that these antibodies were functional, i.e. they affected juvenile immunity. These results suggest that the role of maternal antibodies may depend on the timing and pattern of offspring exposure to parasites, along with the patterns of maternal exposure and the dynamics of her immune response. Overall, our approach underlines that although the transgenerational transfer of antibodies in natural populations is likely to have broad implications, the nature of these effects may vary dramatically among host-parasite systems, depending on the physiological mechanisms involved and the ecological context.

Gynecologists and the abortion issue in Serbia

Traditional inefficient contraception, incorporated to a large extent in the system of values, has become a natural part of sexual relations in Serbia and represents a rational preventive choice from the individual standpoint. However, when pregnancy is unwanted or cannot be accepted out of any reasons abortion is used as a resort. For this reason there is a long history of a large number of abortions in Serbia. Research findings in our country identify the following, as the most important factors for not accepting modern values in this sphere: traditional contraception and abortion have a firm social confirmation; there is a trans-generational transfer of psychological resistance towards the use of combined oral contraception pills and intrauterine devices; sexual education has never become a natural way of growing up in the family, nor is a constituent part of school programs and that distinct obstacles of various nature exist regarding contraception availability. A developed network of various types of family planning counseling is an important determinant of the accessibility of contraceptive means and methods. There are, however, numerous conditions which have to be fulfilled in order for the contraception counseling services to function properly. Among them, motivated personnel who acquired general and specific knowledge for work in this field are an especially important prerequisite. This theoretical assumption opens the question -whether gynecologists represent an important factor of slow transition of birth control in Serbia? We searched for the answer in the research analyses obtained through two in-depth surveys which either had to do with this theme or tried to determine the knowledge, attitude and practice of gynecologists. The first research regarding the determination of the causes for a large number of abortions in our country, was directed towards women who decided on abortion. Gynecologists were the target group in the second research which was KAP type. The results of both researches clearly indicate that gynecologists generally observed, contribute to maintaining the abortion culture and slow transition of birth control from the use of traditional contraception to reliance on modern contraception means and methods in Serbia. Namely, a significant number of gynecologists in our country are at variance with the principals of modern family planning. Their knowledge, attitudes and practice relevant for individual contraceptive choices are insufficient, conservative and inadequate. Thus, there is a necessity for special education of doctors especially gynecologists, at all levels from the basic studies, through specialists ones, to special target courses, seminars, symposiums and conferences. Knowledge acquisition, as the basic element of consciousness can affect formation of standpoints, motivation, promote responsibility and create the requirement for promoting a different system of values and philosophy of living in the sphere of reproductive health.

Status and conservation of the reptiles and amphibians of the Bermuda islands

Bermuda's herpetofauna includes three species of amphibians, one fossil tortoise, two species of freshwater turtles, five species of marine turtles, and four species of lizards. The amphibians Eleutherodactylus johnstonei , E. gossei and Bufo marinus were all introduced in the late 1880s. Amphibian population declines, including the possible extirpation of E. gossei , prompted the initiation in 1995 of an on-going investigation. Research into the high deformity rates in B. marinus has indicated that survival and development of larvae are affected by contaminants in a number of ponds and by the transgenerational transfer of accumulated contaminants. Of the two emydid turtles in Bermuda, Malaclemys terrapin may be native and its population characteristics are being studied; Trachemys scripta elegans is considered invasive and efforts are underway to remove its populations from the wild. The sizeable resident Chelonia mydas population has been the focus of a mark-recapture study since 1968. Results indicate that Bermuda is currently an important developmental habitat for green turtles originating from at least four different nesting beaches in the Caribbean. Immature Eretmochelys imbricat a also reside on the Bermuda Platform and genetics studies suggest that multiple Caribbean genotypes are represented in Bermuda's hawksbill population. Caretta caretta do not appear to be regular inhabitants, but two known loggerhead nesting events have recently occurred (in 1990 and 2005) and post-hatchling loggerheads regularly strand after winter storms. Dermochelys coriacea are only occasionally seen and the last record for a live Lepidochelys kempi in Bermuda occurred in 1949. Three of the lizard species are introduced Anolis ; A. grahami g rahami , A. leachii , and A. extremus . Their populations appear stable and they are presently not being studied. The fourth lizard, the Bermuda skink Eumeces longirostris , is Bermuda's only endemic terrestrial vertebrate. It is classified as Critically Endangered on the IUCN Red List and is protected under the Protected Species Act (2003); much research has been undertaken recently to aid the development of effective conservation management plans for this species.

Inheriting the Holocaust: Transfer of Trauma in Doron Rabinovici’s Suche nach M

Psychologists have observed that unresolved Holocaust traumas can be passed from survivors to their children. This phenomenon, termed trans-generational transfer of trauma, is also evident in some literary works of second-generation authors. This essay provides a brief introduction to the theory of trans-generational transfer of trauma and shows how it can provide another way of reading the literature of second-generation authors, such as Doron Rabinovici’s first novel, Suche nach M. (1999).

L’accouchement : un événement psychique

The psychic process of maternity is a widely recognized and studied mechanism, and its diachronic aspect has been the most frequently described. The present study focusses on the moment of expulsion, and we have attempted to determine the reactions that take place at a psychic level both in the mother and child during the process of childbirth. Expulsion, an act that marks the separation between two bodies has its psychic aspect, denoted by what Freud referred to as “a sense of hatred”, in which what was until then contained within undergoes a movement towards its being expelled, and is then finally expelled outside, an experience which inaugurates the first within–without distinction. Pierra Aulagnier’s conceptualization of the life of the psyche provides a means of representing the mother’s rediscovery during childbirth of suppressed psychic material associated with her own infantile history, that of her own birth, a rediscovery which is only made possible by the process of regression that is characteristic of maternity. The maternal psyche thus serves as a mould for the infant, who will utilize this pictogram of birth transmitted by his mother to come to terms with and represent the process of upheaval that he is experiencing. In Freudian terms, as expulsion gives rise to the psychic experience during this movement of a “a sense of hatred”, we thus postulate that a transgenerational transfer of this birth pictogram may take place – or in other words, a “pictogram of a sense of hatred” — and that this representation provides childbirth with an additional psychic dimension.

Variability in the frequency of sister-chromatid exchange in larvae of Mytilus edulis: implications for field monitoring

Striking variation in the frequency of sister-chromatid exchange (SCE) was detected in progeny of different groups of field-collected and control Mytilus edulis adults. The results demonstrate that there is no intrinsic limit to the frequency of occurrence of SCE in mussel larvae. The results imply that the mussel larval SCE assay may have greater sensitivity than indicated by previous studies of SCE induction by direct exposures of larvae to SCE-inducing chemicals. In addition, although the cause of the high SCE frequencies is unknown, the observations indicate that direct analysis of transgenerational transfer of genotoxic agents should be performed. With further study, this assay may be useful in detecting environmental exposures to genotoxic contaminants.