Full Sisters Research Articles

A Home on the Hill: Memories of St Vincent’s Home, Drexel Hill, PA

A Home on the Hill:Memories of St Vincent’s Home, Drexel Hill, PA Lou Baldwin (bio) The year 1920 started off very badly for the Marra family, Italian immigrants and their six children living in Bethlehem, PA. After the mother died the father abandoned the children and other relatives could not care for them. Because Bethlehem was then part of the Archdiocese of Philadelphia, the authorities brought the children down to Philadelphia and the Catholic Children’s Bureau for placement.1 The children, five girls and a boy were sent to St. Vincent’s Home, Drexel Hill under the charge of the Daughters of Charity. The five girls would stay long-term although Petronilla, the eldest, who did not adjust easily, was for a time placed in foster care, but she was treated so badly she ran away and begged to be taken back at St. Vincent’s. She, Nicky, Flossy, Margaret, and Mary then stayed until they came of age to go off on their own. Most married, raised families, and prospered. Nicky at age 16 chose to remain as paid kitchen staff, eventually head cook, and was a beloved fixture at St Vincent’s until it closed. Their memories and those of other former residents and some of the Sisters are recorded in “We Called it Home: St. Vincent’s Drexel Hill,” compiled by Martin F. Whalen, Jr. whose mother was Petronilla Marra Whalen. It was self-published as a spiral-bound volume in 2003. Most of the seventy or so testimonies were given by elderly matrons (some now deceased) who were recalling events of well over half a century past [End Page 91] with the rest contributed by equally elderly Daughters of Charity. It is entirely possible their memories softened after the passage of time, or others who had sharply different memories chose not to contribute. Nevertheless, these testimonies taken from lived experience should be part of the conversation as to how to meet the needs of children at risk, even if they are at odds with current social theory. By coincidence, St. Vincent’s Home, Drexel Hill opened in 1920, the same year the Marra children arrived; its dedication was held on May 9, 1920 by Archbishop Dennis Dougherty before a throng of 125,000. Pennsylvania Governor William C. Sproul remarked, “I have a good bit of experience in addressing multitudes of our people, but I have never seen a crowd like this.”2 Click for larger view View full resolution Sister with twins Photo courtesy of Martin Whelan The impressive building with a capacity of 550 residents did not represent a brand-new institution, but was the latest of several sites. It had its beginnings in 1855 as an orphanage conducted by the Daughters of Charity on a much smaller scale at Eighteenth and Wood Streets, [End Page 92] Philadelphia and then in 1903 at Twentieth and Race Streets. That property was taken by eminent domain by the city for the construction of the Benjamin Franklin Parkway in 1917. The new 35-acre site was a former summer estate of financier Anthony Drexel, founder of Drexel University and uncle of St. Katharine Drexel. It was obtained almost immediately by Philadelphia’s Archbishop Edmond Prendergast who did not live to see the project to completion because the outbreak of World War I prevented most civilian construction. In the meantime, children from the former St. Vincent’s were sent to a property in Point Pleasant, New Jersey or absorbed by other orphanages in the Archdiocesan system. Catholic orphan care in Philadelphia traces back to 1797 in the wake of the disastrous Yellow Fever epidemic that decimated the city and left many orphans. At first children were placed in an early form of foster care, but in 1806 a matron was hired to care for them and in 1811 three Sisters of Charity (as they were then known) were sent by St. Elizabeth Ann Seton to care for the children. All of the works of the Sisters in Philadelphia follow from that, including St. Vincent’s Home and another St. Vincent’s Home attached to St. Vincent’s Maternity Hospital at 70th Street and Woodland Avenue, Philadelphia...

Sibling relatedness and social play in juvenile ground squirrels

We described the relationship between relatedness as full or maternal half siblings and expression of social play and other social behaviors in juvenile Belding’s ground squirrel (Urocitellus beldingi) litters and evaluated the possible role of play in establishing social bonds between juvenile females. We used microsatellite analysis to determine relatedness. Juvenile females did not interact preferentially with full over half siblings, suggesting that they may form bonds equally with full and half sisters. The probability that females will have a surviving full sister beyond the juvenile period may be low in U. beldingi, and establishing a cooperative relationship with a half sister may sometimes be the best available option in adulthood. As the proportion of females within litters increased, rates of play decreased, suggesting that low social play may be adequate for social bonding among females. Among juvenile male U. beldingi, play bouts lasted longer between full than half brothers; however, juvenile males did not interact preferentially with full brothers in play or other social interactions. Body mass differences were smaller between full than half brothers, and in both full and half brother pairings, play bouts lasted longest when body mass differences were small. Because male U. beldingi do not ordinarily interact with littermate siblings after emigrating from the natal area, it is unlikely that play behavior functions to establish long-term social bonds between full brothers. Rather, young males may favor play interactions with phenotypically similar partners who can provide optimal challenges in interactions that promote motor development.

Evolution of paternal care in diploid and haplodiploid populations.

W. D. Hamilton famously suggested that the inflated relatedness of full sisters under haplodiploidy explains why all workers in the social hymenoptera are female. This suggestion has not stood up to further theoretical scrutiny and is not empirically supported. Rather, it appears that altruistic sib-rearing in the social hymenoptera is performed exclusively by females because this behaviour has its origins in parental care, which was performed exclusively by females in the ancestors of this insect group. However, haplodiploidy might still explain the sex of workers if this mode of inheritance has itself been responsible for the rarity of paternal care in this group. Here, we perform a theoretical kin selection analysis to investigate the evolution of paternal care in diploid and haplodiploid populations. We find that haplodiploidy may either inhibit or promote paternal care depending on model assumptions, but that under the most plausible scenarios it promotes - rather than inhibits - paternal care. Our analysis casts further doubt upon there being a causal link between haplodiploidy and eusociality.

Bumble bee workers drift to conspecific nests at field scales

1. Workers in several bee species travel to conspecific nests (‘drifting’), enter them, and produce male offspring inside them, so acting as intra‐specific social parasites. This adds a new dimension to bees' reproductive behaviour and spatial ecology, but the extent to which drifting occurs over field scales, i.e. at natural nest densities in field conditions, has been unclear.2. Using the bumble bee Bombus terrestris (Linnaeus) as a model system, we sought to determine rates of worker drifting at field scales and the frequency of potential drifter workers in wild nests.3. A field experiment with 27 colonies showed that workers travelled to, and became accepted in, conspecific nests that were up to 60 m away, although the number of accepted drifter workers within nests fell significantly with distance. The rate at which nests were entered by drifters was relatively high and significantly exceeded the rate at which drifters became accepted.4. Microsatellite genotyping of eight field‐collected nests from Greater London, U.K., showed that a low frequency (3%) of workers were not full sisters of nestmate workers and hence were likely to have been drifter workers.5. It is therefore concluded that workers can drift to conspecific nests over field scales and confirmed that successful drifting occurs in natural populations. Drifting appears to be a natural but low‐frequency behaviour permitting B. terrestris workers to gain direct fitness.

Haplodiploidy and the Evolution of Eusociality: Worker Reproduction

Hamilton's haplodiploidy hypothesis suggests that the relatively higher relatedness of full sisters in haplodiploid populations promotes altruistic sib rearing and, consequently, the evolution of eusociality. This haplodiploidy effect works when some broods have a relatively female-biased sex ratio and other broods have a relatively male-biased sex ratio, termed split sex ratios. There is empirical evidence for two scenarios having potentially led to split sex ratios en route to eusociality: unmated queens and queen replacement. A recent analysis of these two scenarios has suggested that haplodiploidy can either promote or inhibit the evolution of eusociality and that the effect is usually small. However, this work made the simplifying assumptions that there is only negligible reproduction by workers and that their offspring have the same sex ratio as those produced by the queen. Here, we relax these assumptions and find that worker reproduction has a negative influence on the evolution of helping, either reducing the extent to which it is promoted or leading to it being inhibited. This is particularly so when workers are unmated and hence constrained to produce only sons, by arrhenotoky. Overall, when parameterized with empirical data, our results suggest that split sex ratios in haplodiploid species have not played an important role in facilitating the evolution of eusociality.

Social influences on body size and developmental time in the bumblebee Bombus terrestris

In many social insects, including bumblebees, the division of labor between workers relates to body size, but little is known about the factors influencing larval development and final size. We confirmed and extend the evidence that in the bumblebee Bombus terrestris the adult bee body size is positively correlated with colony age. We next performed cross-fostering experiments in which eggs were switched between incipient (before worker emergence) and later stage colonies with workers. The introduced eggs developed into adults similar in size to their unrelated nestmates and not to their same-age full sisters developing in their mother colony. Detailed observations revealed that brood tending by the queen decreases, but does not cease, in young colonies with workers. We next showed that both worker number and the queen presence influenced the final size of the developing brood, but only the queen influence was mediated by shortening developmental time. In colonies separated by a queen excluder, brood developmental time was shorter in the queenright compartment. These findings suggest that differences in body size are regulated by the brood interactions with the queen and workers, and not by factors inside the eggs that could vary along with colony development. Finally, we developed a model showing that the typical increase in worker number and the decrease in brood contact with the queen can account for the typical increase in body size. Similar self-organized social regulation of brood development may contribute to the optimization of growth and reproduction in additional social insects.

Genetic variation in MKL2 and decreased downstream PCTAIRE1 expression in extreme, fatal primary human microcephaly

The genetic mechanisms driving normal brain development remain largely unknown. We performed genomic and immunohistochemical characterization of a novel, fatal human phenotype including extreme microcephaly with cerebral growth arrest at 14–18 weeks gestation in three full sisters born to healthy, non-consanguineous parents. Analysis of index cases and parents included familial exome sequencing, karyotyping, and genome-wide single nucleotide polymorphism (SNP) array. From proband, control and unrelated microcephalic fetal cortical tissue, we compared gene expression of RNA and targeted immunohistochemistry. Each daughter was homozygous for a rare, non-synonymous, deleterious variant in the MKL2 gene and heterozygous for a private 185 kb deletion on the paternal allele, upstream and in cis with his MKL2 variant allele, eliminating 24 CArG transcription factor binding sites and MIR4718. MKL1 was underexpressed in probands. Dysfunction of MKL2 and its transcriptional coactivation partner, serum response factor (SRF), was supported by a decrease in gene and protein expression of PCTAIRE1, a downstream target of MKL2:SRF heterodimer transcriptional activation, previously shown to result in severe microcephaly in murine models. While disruption of the MKL2:SRF axis has been associated with severe microcephaly and disordered brain development in multiple model systems, the role of this transcription factor complex has not been previously demonstrated in human brain development.

Mammographic density and breast cancer: a comparison of related and unrelated controls in the Breast Cancer Family Registry

IntroductionPercent mammographic density (PMD) is a strong and highly heritable risk factor for breast cancer. Studies of the role of PMD in familial breast cancer may require controls, such as the sisters of cases, selected from the same 'risk set' as the cases. The use of sister controls would allow control for factors that have been shown to influence risk of breast cancer such as race/ethnicity, socioeconomic status and a family history of breast cancer, but may introduce 'overmatching' and attenuate case-control differences in PMD.MethodsTo examine the potential effects of using sister controls rather than unrelated controls in a case-control study, we examined PMD in triplets, each comprised of a case with invasive breast cancer, an unaffected full sister control, and an unaffected unrelated control. Both controls were matched to cases on age at mammogram. Total breast area and dense area in the mammogram were measured in the unaffected breast of cases and a randomly selected breast in controls, and the non-dense area and PMD calculated from these measurements.ResultsThe mean difference in PMD between cases and controls, and the standard deviation (SD) of the difference, were slightly less for sister controls (4.2% (SD = 20.0)) than for unrelated controls (4.9% (SD = 25.7)). We found statistically significant correlations in PMD between cases (n = 228) and sister controls (n = 228) (r = 0.39 (95% CI: 0.28, 0.50; P <0.0001)), but not between cases and unrelated controls (n = 228) (r = 0.04 (95% CI: -0.09, 0.17; P = 0.51)). After adjusting for other risk factors, square root transformed PMD was associated with an increased risk of breast cancer when comparing cases to sister controls (adjusted odds ratio (inter-quintile odds ratio (IQOR) = 2.19, 95% CI = 1.20, 4.00) or to unrelated controls (adjusted IQOR = 2.62, 95% CI = 1.62, 4.25).ConclusionsThe use of sister controls in case-control studies of PMD resulted in a modest attenuation of case-control differences and risk estimates, but showed a statistically significant association with risk and allowed control for race/ethnicity, socioeconomic status and family history.

Abstract 4018: Whole exome sequencing analysis of familial Medulloblastoma.

Abstract Medulloblastoma (MB) is the most common malignant brain cancer in children. Although MB can be categorized into four distinct subtypes, the underlying genetic changes required to promote MB remain unclear. We performed whole exome sequencing was performed on germ-line DNA from two affected cousins who were diagnosed at similar ages with classic WNT subtype MB, and their unaffected mothers, who are full sisters. We found cousins to be homozygous for a variant in a gene regulating WNT-signaling (variant 1), while their mothers were heterozygous. In a mouse model of WNT-type MB, incomplete penetrance and the requirement for inactivation of TP53 were observed. We, therefore, hypothesized that a deleterious mutation in the TP53 pathway may be present. Indeed, we found a single copy of a novel mutation in a regulator of TP53 shared between the affected cousins (variant 2). This allele segregated through the cousins’ maternal line as evidenced by both mothers being heterozygous for this allele. Finally, we identified a common homozygous variant in a gene involved in promoting RAS-mediated cell proliferation (variant 3). We found that mutations in the genes of variants 1 and 3 have been previously reported to be involved in sporadic MB, suggesting that what we observe in this family translates to sporadic disease. Thus, our model for MB development is that of a threshold effect in which combinations of both familial and common variants interact to increase susceptibility. We hypothesize that this model with incomplete penetrance may underlie cancer susceptibility in many families with apparent cancer predisposition syndromes but in whom no causative mutation has been identified. We also hypothesize that this multi-gene model with incomplete penetrance may also explain a proportion of apparently sporadic cases of cancer. This work underscores the advantages of analyzing sequence data from multiple well-chosen affected and unaffected individuals in well-chosen families for gene discovery in cancer and other complex diseases. It also puts forth a new model for analysis, incorporating both agnostic and hypothesis driven models using data from the literature and complementary datasets. Citation Format: Mark M. Sasaki, Andrew D. Skol, Trevor J. Pugh, Matthew Meyerson, Kenan Onel. Whole exome sequencing analysis of familial Medulloblastoma. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 4018. doi:10.1158/1538-7445.AM2013-4018

Paternal Relatedness Predicts the Strength of Social Bonds among Female Rhesus Macaques

Forming strong, equitable, and enduring social bonds with a few individuals in a group carries adaptive benefits in terms of increased longevity, offspring survival and paternity success in birds and mammals, including humans. These recent insights generated a new interest in the factors creating variation in the strength of social relationships. Whether and how animals discriminate paternal kin from non-kin and bias their social behavior accordingly is being debated. This study explores the relative importance of dominance rank, age, maternal and paternal relatedness in shaping dyadic affiliative relationships in a group of 30 captive rhesus macaque females. The strength of social relationships, measured by the composite sociality index from observational data, was independently predicted in GLMMs by both maternal and paternal relatedness as well as rank similarity. In addition, social bonds between paternal half-sisters were stronger than between distantly related kin suggesting that females biased their affiliative effort towards paternal relatives. Despite identical relatedness coefficients bonds between mothers and their daughters were three times as strong as those between full sisters. Together these results add to the growing body of evidence for paternal kin biases in affiliative behavior and highlight that females prefer descendent over lateral kin.

Why Wasp Foundresses Change Nests: Relatedness, Dominance, and Nest Quality

The costs and benefits of different social options are best understood when individuals can be followed as they make different choices, something that can be difficult in social insects. In this detailed study, we follow overwintered females of the social wasp Polistes carolina through different nesting strategies in a stratified habitat where nest site quality varies with proximity to a foraging area, and genetic relatedness among females is known. Females may initiate nests, join nests temporarily or permanently, or abandon nests. Females can become helpers or egglayers, effectively workers or queens. What they actually do can be predicted by a combination of ecological and relatedness factors. Advantages through increased lifetime success of individuals and nests drives foundresses of the social wasp Polistes from solitary to social nest founding. We studied reproductive options of spring foundresses of P. carolina by monitoring individually-marked wasps and assessing reproductive success of each foundress by using DNA microsatellites. We examined what behavioral decisions foundresses make after relaxing a strong ecological constraint, shortage of nesting sites. We also look at the reproductive consequences of different behaviors. As in other Polistes, the most successful strategy for a foundress was to initiate a nest as early as possible and then accept others as subordinates. A common feature for many P. carolina foundresses was, however, that they reassessed their reproductive options by actively monitoring other nests at the field site and sometimes moving permanently to new nests should that offer better (inclusive) fitness prospects compared to their original nests. A clear motivation for moving to new nests was high genetic relatedness; by the end of the foundress period all females were on nests with full sisters.

Similarity in Food Cleaning Techniques within Matrilines in Wild Vervet Monkeys

Social learning and the formation of traditions rely on the ability and willingness to copy one another. A central question is under which conditions individuals adapt behaviour to social influences. Here, we demonstrate that similarities in food processing techniques emerge on the level of matrilines (mother – offspring) but not on the group level in an experiment on six groups of wild vervet monkeys that involved grapes covered with sand. Monkeys regularly ate unclean grapes but also used four cleaning techniques more similarly within matrilines: rubbing in hands, rubbing on substrate, open with mouth, and open with hands. Individual cleaning techniques evolved over time as they converged within matrilines, stabilised at the end and remained stable in a follow-up session more than one year later. The similarity within matrilines persisted when we analyzed only foraging events of individuals in the absence of other matriline members and matriline members used more similar methods than adult full sisters. Thus, momentary conversion or purely genetic causation are unlikely explanations, favouring social learning as mechanism for within matriline similarities. The restriction of traditions to matriline membership rather than to the group level may restrict the development of culture in monkeys relative to apes or humans.

Colony structure and reproductive sharing among queens in a tropical paper wasp, Polistes olivaceus

Reproductive partitioning among group members is a key feature in social Hymenoptera. We investigated the genetic colony structure of a tropical paper wasp Polistes olivaceus, with an emphasis on variation in the number of queens and reproductive sharing among queens. Among 22 P. olivaceus colonies, 6 were monogynous, 9 polygynous, and 7 were queenless. Adults and brood (eggs and larvae) were genotyped based on six polymorphic microsatellite loci. In each of the polygynous colonies, progenies were assigned to their mothers using maximum-likelihood methods. Nestmate queens were full sisters. The vast majority of reproduction appeared to be monopolized by the dominant queen (α), and the overall reproductive skews were 0.63 ± 0.04 (B index) and 0.97 ± 0.02 (S c index). Although all nestmate queens had equal reproductive potential, the high magnitude of reproductive skew was enigmatic in this species. Although 9.55 ± 2.07 workers contained developed ovaries in 11 of 15 queen-right colonies, they were unrelated to the nestmate queens but related to each other as full sisters, suggesting that they were the remaining offspring of superseded queens. In 2 of the 11 colonies, we detected male eggs produced by reproductive workers. On average, 7.27 % of the total genotyped male eggs were derived from reproductive workers among the colonies. These results suggest three possibilities regarding the presence of reproductive workers in the P. olivaceus colonies: drifting between colonies, putative remaining offspring from superseded queens, and the offspring of unrelated females who joined the colonies and reproduced there. We found no worker-derived larvae or adult males, suggesting that male eggs were removed by nestmates at some point between oviposition and hatching.

Incest Laws and Absent Taboos in Roman Egypt

For at least two hundred and fifty years, many men in the Roman province of Egypt married their full sisters and raised families with them. During the same era, Roman law firmly banned close-kin marriages and denounced them both as nefas, or sacrilegious, and against the ius gentium, the laws shared by all civilized peoples. In Egypt, however, Roman officials deliberately chose not to enforce the relevant marriage laws among the Greek metic, hybrid, and native Egyptian populations; the bureaucracy also created loopholes within new laws which tolerated the practice. This policy created a gap between the absolute theoretical ban in Roman law and the reality of common incestuous unions in Egypt. Since Roman Egypt was both an important and a dangerous province, Rome needed both to pacify its people and to weaken Egypt’s status with its neighbors. By permitting incestuous marriages among non-Romans in Egypt, the Roman governors simultaneously pleased the local population while causing Jews and North Africans to hold their neighbor in contempt.

Edward the Confessor: The Man and the Legend

The papers in this volume were delivered in 2005, at a conference commemorating the millennium of Edward the Confessor's birth, sometime between 1002, when his parents were married, and 1005, when his first attestation appears on one of his father's diplomas. The uncertainty exemplifies the shortcomings of Old English source material, exacerbated in Edward's case by what one of the contributors calls the ‘1066 effect’ (p. 135), in which retrospective attempts to explain and excuse the impact of the Norman Conquest project more heat than light on the last years of the Old English kingdom. All the contributions to this volume are duly critical of the sources, and make great efforts to pluck the few facts from the luxuriant growth of plausible fictions. Richard Mortimer's opening paper, bearing the same title as the volume itself, attempts to separate the eleventh-century king from the posthumously culted saint, though admitting that ‘the man and the legend, at the most basic level, cannot be disentangled’ (p. 39). Mortimer gives an admirably clear overview of Edward's life, leaving his co-contributors to concentrate on particular themes. Simon Keynes (‘Edward the ætheling’) deals with the most obscure period, Edward's boyhood and adolescence in the England of Æthelred unræd, noting (like Mortimer) the mismatch between the scanty contemporary notices and later literary traditions. Elisabeth van Houts’ paper, ‘Edward and Normandy’, covers Edward's exile, concentrating on the roles of his full sister Godgifu, and her husband, Drogo, count of the Vexin; they were patrons of Saint-Wandrille, Saint-Ouen of Rouen, and Jumièges, all houses which actively promoted Edward's claims to the English throne. The career of the other woman in Edward's life is covered by Pauline Stafford (‘Edith: Edward's wife and queen’), who argues that the king's marriage was a full union intended to produce heirs, which, for some reason, failed in its purpose. Her paper is especially important for its discussion of the Vita Ædwardi regis, widely regarded as an important source for Edward's reign; her dating of the entire work to the period after 1066 is therefore crucial, for it undermines the reliability of its testimony by placing it in the post-Conquest world of controversy and special pleading, where, in the clamour of conflicting and contradictory voices, the issues of Edward's reign are obscured not by the paucity of the sources but by their very abundance. In the case of the royal succession, indeed, some modern commentators have rejected the whole corpus of evidence as ‘a tissue of lies’ (p. 80). Stephen Baxter is not prepared to go so far, and his paper on ‘Edward the Confessor and the succession question’ avoids rehearsing post-Conquest claims and counter-claims, choosing rather to reconstruct the changing political events of the reign, and thus ‘build up a more informed view as to whether Edward was ever in a position to make the choices attributed to him’ (p. 82). Baxter's analysis, based largely on the surviving charters, concludes that Edward's ‘handling of the succession was dangerously indecisive and contributed to one of the greatest catastrophes to which the English have ever succumbed’ (p. 118).

Estimation of bumblebee queen dispersal distances using sibship reconstruction method

Dispersal ability is a key determinant of the propensity of an organism to cope with habitat fragmentation and climate change. Here we quantify queen dispersal in two common bumblebee species in an arable landscape. Dispersal was measured by taking DNA samples from workers in the spring and summer, and from queens in the following spring, at 14 sites across a landscape. The queens captured in the spring must be full sisters of workers that were foraging in the previous year. A range of sibship reconstruction methods were compared using simulated data sets including or no genotyping errors. The program Colony gave the most accurate reconstruction and was used for our analysis of queen dispersal. Comparison of queen dispersion with worker foraging distances was used to take into account an expected low level of false identification of sister pairs which might otherwise lead to overestimates of dispersal. Our data show that Bombus pascuorum and B. lapidarius queens can disperse by at least 3 and 5 km, respectively. These estimates are consistent with inferences drawn from studies of population structuring in common and rare bumblebee species, and suggest that regular gene flow over several kilometres due to queen dispersal are likely to be sufficient to maintain genetic cohesion of ubiquitous species over large spatial scales whereas rare bumblebee species appear unable to regularly disperse over distances greater than 10 km. Our results have clear implications for conservation strategies for this important pollinator group, particularly when attempting to conserve fragmented populations.

Maternal Contributions to Preterm Delivery

Preterm delivery (PTD) is a complex trait with a significant familial component. However, no specific inheritance patterns have been established. The authors examined the contribution of PTDs in both the woman's family and her partner's family to her risk of PTD. The authors linked birth information from Danish national registers with pedigree information from the Danish Family Relations Database for 1,107,124 live singleton deliveries occurring from 1978 to 2004. Risk ratios were estimated comparing women with and without various PTD histories. Women with previous PTDs were at greatly increased risk of recurrent PTD (risk ratio = 5.6, 95% confidence interval: 5.5, 5.8); however, their PTD risk was unaffected by a partner's history of preterm children with other women. PTDs to a woman's mother, full sisters, or maternal half-sisters also increased her PTD risk (risk ratio = 1.6, 95% confidence interval: 1.5, 1.6), whereas PTDs in her paternal half-sisters, the female partners of her male relatives, or members of her partner's family did not affect her PTD risk. Inheritance patterns were similar for all gestational ages from very early through late PTD. The substantial portion of PTD risk explained by effects passed through the female line suggests a role for either imprinting or mitochondrial inheritance.

Detecção de QTL em dados de famílias estruturadas como as de um núcleo MOET por meio do método da regressão

O objetivo deste trabalho foi avaliar a eficiência do método de regressão em detectar QTL com base na utilização de dados da estrutura de família (irmãos completos e meios-irmãos), como aqueles gerados em um núcleo MOET. Foram simulados dados fenotípicos e genotípicos em uma estrutura de núcleo MOET fechado de seleção. Três arquivos foram analisados, contendo: a) informações conjuntas de irmãos completos e meios-irmãos; b) apenas informações de irmãos completos e c) apenas informações de meios-irmãos. Verificou-se que o método da regressão, para dados discretos ou contínuos, foi capaz de detectar associações entre marcador e QTL em níveis bastante expressivos de significância (P&lt;0.001 e P&lt;0,0001), quando se utilizou o arquivo que continha informações conjuntas de irmãos completos e meios-irmãos. Os resultados indicaram a possibilidade de utilização dessa metodologia para estudos de detecção/validação de QTL em rebanhos ou núcleos de seleção que utilizam MOET.

Ploidy of the eusocial beetle Austroplatypus incompertus (Schedl) (Coleoptera, Curculionidae) and implications for the evolution of eusociality

In the hymenopterans, haplodiploidy, leading to high-genetic relatedness amongst full sisters has been regarded as critical to kin selection and inclusive fitness hypotheses that explain the evolution of eusociality and altruistic behaviours. Recent evidence for independent origins of eusociality in phylogenetically diverse taxa has led to the controversy regarding the general importance of relatedness to eusociality and its evolution. Here, we developed a highly polymorphic microsatellite marker to test whether the eusocial ambrosia beetle Austroplatypus incompertus (Schedl) is haplodiploid or diplodiploid. We found that both males and females of A. incompertus are diploid, signifying that altruistic behaviour resulting from relatedness asymmetries did not play a role in the evolution of eusocialty in this species. This provides additional evidence against the haplodiploidy hypothesis and implicates alternative hypotheses for the evolution of eusociality.

Single mating in orchid bees (Euglossa, Apinae): implications for mate choice and social evolution

Neotropical orchid bees (Euglossini) are conspicuously different from other corbiculate bees (Apinae) in their lack of advanced sociality and in male use of acquired odors (fragrances) as pheromone-analogues. In both contexts, orchid bee mating systems, in particular the number of males a female mates with, are of great interest but are currently unknown. To assess female mating frequency in the genus Euglossa, we obtained nests from three species in Mexico and Panama and genotyped mothers and their brood at microsatellite DNA loci. In 26 out of 29 nests, genotypes of female brood were fully consistent with being descended from a singly mated mother. In nests with more than one adult female present, those adult females were frequently related, with genotypes being consistent with full sister–sister (r = 0.75) or mother–daughter (r = 0.5) relationships. Thus, our genetic data support the notions of female philopatry and nest-reuse in the genus Euglossa. Theoretically, single mating should promote the evolution of eusociality by maximizing the relatedness among individuals in a nest. However, in Euglossini this genetic incentive has not led to the formation of eusocial colonies as in other corbiculate bees, presumably due to differing ecological or physiological selective regimes. Finally, monandry in orchid bees is in agreement with the theory that females select a single best mate based on the male fragrance phenotype, which may contain information on male age, cognitive ability, and competitive strength.