Unknown Donor Research Articles

Clonality in black locust (Robinia pseudoacacia L.) and implications for seed production

Key messageThe strong clonal growth of black locust (Robinia pseudoacacia L.) not only influences the stand structure of natural or artificially established stands, but also the genetic composition of seed harvested from such clonal stands. For the commercial production of genetically diverse seeds, the stand structure should be taken into account or, at best, seeds harvested from seed orchards should be used.ContextBlack locust is characterised by intensive asexual reproduction through the formation of root suckers. By this means clonal structures can develop within black locust stands, in which ramets of a single clone can dominate extensive areas.AimsWe want to analyse to what extent clonal structures within black locust stands negatively influence the genetic composition and diversity in seed harvested in such stands. We discuss how a potential reduction in genetic diversity can be reduced by measures taken during harvesting and whether the harvesting of seed orchards may be a better alternative.MethodsWe compare the genetic composition and diversity of parent trees and seed harvested from a clonal black locust stand with a seed orchard in which multiple ramets of selected clones were arranged in a randomised design.ResultsWithin the clonal stand, parent contributions to the seed lot analysed proved to be strongly uneven. Selfing rates were high and large full-sib families dominated within the seed lot. Although the relatively strong pollination from unknown pollen donors, probably located outside of the stand, prevented a massive loss of alleles, high selfing rates and the formation of large full-sib families led to an unequal distribution of alleles within the progeny. Within the seed orchard—even though it had a lower number of clones than expected—the randomised design promoted a more diverse pollination pattern.ConclusionWe conclude that for black locust, seed orchards have the greater potential to ensure a balanced genetic composition of harvested seed lots. If economic considerations make it necessary to harvest seed stands, this should only be done in a considered manner and, if possible, with knowledge of the clonal structures of the stand.

P-496 Being a solo mother: an exploration of parenting experiences and support needs of women who intentionally choose to become mothers without a partner

Abstract Study question What support sources do solo mothers in the UK use, how supported do they feel and what areas are lacking? Summary answer Most solo mothers feel supported by family, friends and paid childcare and are confident in their parenting despite finding it difficult to ask for help. What is known already An increasingly common family type, often referred to as ‘solo mothers,’ ‘single mothers by choice’ or ‘choice mothers’, is defined by women who intentionally choose to become mothers without the involvement of a partner. Solo mothers are a relatively homogenous group, who are generally well-educated, employed in professional careers, and financially stable, with most becoming mothers in their mid-thirties/forties. Although solo mothers are frequently described as self-determined and motivated individuals with a strong preparedness for parenting that encompasses both economic and social resources, there is a notable absence of research on their specific parenting experiences and support needs. Study design, size, duration A cross-sectional study was conducted using an online survey. The questionnaire was distributed via solo mother-specific Facebook groups and through newsletters, emails and social media of the Donor Conception Network (DCN). A total of 139 participants responded between July 2021 and February 2022. Participants/materials, setting, methods Most participants were aged 36-45 (53%, 74), had one child (73%, 102) under the age of 11 (88%, 140). Almost all solo mothers had used donated sperm from an unknown donor through a clinic or sperm bank (95%, 132) and around a fifth used donated eggs (22%, 31). All quantitative data was treated as non-parametric and were analysed using descriptive statistics and Spearman’s Rho Correlation tests. Open-ended questionnaire responses were analysed using qualitative content analysis. Main results and the role of chance The most commonly used sources of support for solo mothers in the UK were family members (89%, 123) and non-solo mother friends (80%, 110). Paid childcare was used by 71% (98) of participants with solo mothers using it at least a few times per week. Facebook, particularly solo mum-specific groups, and resources from the Donor Conception Network (DCN, a support organisation for families formed using donor conception) were used by nearly three quarters of respondents (70%, 94 and 71%, 98, respectively). The majority of participants felt supported (78%, 108) but around a quarter (23%, 25) mentioned the need for financial support and the difficulties of relying on a single salary and having to pay for costly childcare. Most solo mums felt confident in their parenting (87%, 122) but found it difficult to ask for help from others (56%, 77). Barriers to asking for help included challenges to autonomy and self-identity, inability to recognise the need for support, fear and apprehension with others, and the emotional aspect of asking for support. There were positive correlations between feeling supported and confidence in parenting (ρ = 0.405, p <.001) and feeling supported and ease in asking for help (ρ = 0.458, p <.001). Limitations, reasons for caution The use of solo mother-specific Facebook groups and DCN resources to recruit solo mothers may have introduced some bias in the sampling methods which may have led to our participants not being more broadly representative of UK solo mothers. Wider implications of the findings Whilst solo mothers may typically be highly educated and financially stable, this is not always the case. Some face challenges in accessing and paying for practical and emotional support. Future research should address provision of better support, given the increasing numbers of solo mother families in the UK and elsewhere. Trial registration number not applicable

P-712 A national survey of women’s perspectives and experiences of pursuing donor eggs

Abstract Study question What are the experiences of women who consider a donor egg, and the outcomes of those who receive donor eggs for conception? Summary answer Of 255 respondents, 59 women (23.1%) were formally placed on a donor egg waitlist, despite 80.6% respondents considering donor eggs with an IVF clinic (166/206). What is known already There is a shortage of donor eggs worldwide. Oocyte donation is a treatment option that is increasingly used for infertile women, as seen through the percentage of patients undergoing IVF who are over 40 years. Previous international studies report oocyte donation recipients to be predominantly aged 34-40 years, white, nulliparous, well-educated, married and financially secure. Although there are records in Australia for the number of donor and recipient cycles undertaken, there is no published data on the number of patients considering a donor oocyte, or on oocyte donor waitlists. In Australia egg donation is altruistic, non-commercial and not anonymous. Study design, size, duration A 52-point online survey was distributed via social media to women in Australia who had ever considered or pursued donor eggs, or come to the end of their own IVF treatment. The survey was sent to all clinical members of the Fertility Society of Australia and New Zealand (FSANZ) and available on the Victorian Assisted Reproductive Technology Authority (VARTA) website. The survey was open from 1 February to 30 April 2023. Hospital ethics approved. Participants/materials, setting, methods A cross-sectional, anonymous, online survey of women in Australia who were potential egg donor recipients. Survey questions included demographics, potential donor egg recipient preferences, IVF clinic experiences, barriers, any impact of the COVID-19 pandemic, attitudes around the reimbursement for donor eggs, and fertility costs already incurred. Responses were collected via the Qualtrics XM platform. Statistical analysis for quantitative data was analysed using Microsoft 365 Excel. Qualitative coding performed on the commentary in free text fields. Main results and the role of chance This study identified a large gap between those who considered a donor egg (80.6%), pursue a donor egg on an IVF clinic waitlist (23.1%), and those who actually received a donor egg. Of the 59/255 women who were placed on an oocyte donor waitlist at an IVF clinic in Australia, less than a quarter (23.1%) received a donor egg (13/58), with a pregnancy and live birth rate of 76.9% and 61.5%, respectively. Thus, of those that were on an Australian waitlist, one quarter received donor eggs, with over half of these recipients having a live birth. ‘Women preferred donor eggs from Australia than overseas, preferred an unknown donor from an IVF clinic program, and wished to know source information for themselves and children in the future. Attitudes towards financial reimbursement were generally positive towards compensation. Barriers to pursuing donor eggs included grief of loss of own fertility, cost, availability and time. When on an Australian donor egg list, many respondents still looked at other sources of donor eggs in Australia and overseas. Reasons women came off an Australian donor egg waitlist included receiving donor eggs and donor embryos elsewhere, including from overseas, as well as advancing age and expense. Limitations, reasons for caution Risk of respondent selection bias of those who chose to response to a public survey, with incomplete data for some respondents. Given survey in English, may have underrepresentation of some cultural groups and sampling a limited range of women from diverse social, economic and religious settings. Wider implications of the findings In this first paper of potential egg recipients’ preferences in the Asia-Pacific region, we have identified a gap where demand for donor eggs exceeds local supply. A majority of potential recipients would support financial reimbursement for eggs already cryopreserved by women initially freezing for own elective purposes. Trial registration number not applicable

Uncovering ghost introgression through genomic analysis of a distinct eastern Asian hickory species.

Ghost introgression, or the transfer of genetic material from extinct or unsampled lineages to sampled species, has attracted much attention. However, conclusive evidence for ghost introgression, especially in plant species, remains scarce. Here, we newly assembled chromosome-level genomes for both Carya sinensis and Carya cathayensis, and additionally re-sequenced the whole genomes of 43 C. sinensis individuals as well as 11 individuals representing 11 diploid hickory species. These genomic datasets were used to investigate the reticulation and bifurcation patterns within the genus Carya (Juglandaceae), with a particular focus on the beaked hickory C. sinensis. By combining the D-statistic and BPP methods, we obtained compelling evidence that supports the occurrence of ghost introgression in C. sinensis from an extinct ancestral hickory lineage. This conclusion was reinforced through the phylogenetic network analysis and a genome scan method VolcanoFinder, the latter of which can detect signatures of adaptive introgression from unknown donors. Our results not only dispel certain misconceptions about the phylogenetic history of C. sinensis but also further refine our understanding of Carya's biogeography via divergence estimates. Moreover, the successful integration of the D-statistic and BPP methods demonstrates their efficacy in facilitating a more precise identification of introgression types.

#1569 Cytomegalovirus (CMV) infection in renal transplant patients managed with early pre-emptive treatment

Abstract Background and Aims Human Cytomegalovirus (CMV) can cause significant morbidity in transplant recipients. Primary CMV infection in CMV seronegative recipients (R−) and reactivation of CMV in seropositive recipients (R+) post-transplant can lead to CMV end organ disease (EOD). At Royal Free Hospital (RFH), London, United Kingdom, CMV EOD is prevented through pre-emptive therapy (PET), which utilises quantitative real-time PCR (qPCR) in whole blood to monitor all transplant patients and guide therapeutic interventions (1). PET is started in D+R− transplant patients following the first detectable CMV DNA (≥200 copies/ml) in blood (2). For CMV seropositive patients, PET is started when CMV DNA is ≥3000 copies/ml. This differs from many transplant centres which provide CMV anti-viral prophylaxis for the first 3-6 months post-transplant to patients at high risk of developing CMV EOD. In this observational study, the effectiveness of our PET approach and differences in CMV viral replication kinetics was retrospectively analysed in renal transplant recipients of differing CMV serostatus. Method A retrospective review of results from electronic patient records and laboratory information management system for patients who underwent renal transplantation from April 2021 to January 2023 was conducted. Patients were divided into four groups based on organ donor and recipient CMV IgG serostatus (D+R−, D+R+, D−R+, D−R−). Those who were followed up for less than 90 days or had unknown donor serostatuses were excluded. Results A total of 227 patients who received renal transplantation between April 2021 to January 2023 were identified. Of which, 11% (25/227) were D+R−, 42.3% (96/227) were D+R+, 33% (75/227) were D−R+ and 13.7% (31/227) were D−R−. Within each group, 60% (15/25) of D+R−, 61.5% (59/96) of D+R+ and 48% (36/75) of D−R+ patients developed CMV viraemia during the monitoring period. Of CMV viraemic patients, all D+R− (15/15), 54.2% (32/59) of D+R+ and 27.8% (10/36) of D−R+ patients were treated with valganciclovir as per our PET protocol. None of the D−R− patients developed any CMV viraemia. The mean peak viral load for patients with viraemia requiring treatment with valganciclovir was 4772 copies/ml (range 210-30000 copies/ml) in D+R−, 5050 copies/ml (range 3000-30000 copies/ml) and 5050 copies/ml (range 3300-18000 copies/ml) in D+R+ and D−R+ groups respectively. The mean time to first viraemia was 59 days (range 15-332) for the D+R−, 40 days (range 7-177) for D+R+ and 43 days (range 15-91) for D−R+ patients. Furthermore, the mean duration of viraemia was 34 days for D+R−, 37.5 days for D+R+ and 30.5 days for D−R+ groups. 19 patients had CMV viraemia recurrence requiring re-treatment, 63%were D+R− (12/19), 32% were D+R+ (6/19) and 5% (1/19) were D−R+. Across all four groups, two patients developed CMV EOD. One D+R+ patient was found to have CMV in respiratory sample and one D−R+ patient had CMV on colon biopsy. One D+R− patient developed UL97 mutations (M460I and A594V) conferring ganciclovir resistance due to poor compliance and was treated with maribavir. Conclusion PET is a safe and effective approach which reduces the risk of CMV EOD and antiviral medication resistance in SOT patients. Our PET approach provides monitoring of all patients regardless of CMV serostatus thereby reducing the risk of CMV EOD in all patients by ensuring early treatment of viraemia.

Nails as optimal source of DNA for molecular identification of 5 decomposed bodies recovered from seawater: from Y-ancestry to personal identification.

Molecular identification of extremely compromised human remains in forensic field is usually performed from DNA typing of bones, which are a difficult sample to work with. Moreover, autosomal STR profiles do not always result in the identification of the donor due to lack of comparisons or non-hit throughout database searching. An attempt to overcome these issues is represented by fingernails as an alternative DNA source and Y-STRs typing to infer both geographical and familial ancestry of the unknown donor. In this study, we analyzed both 24 autosomal and 27 Y-chromosome STRs from unidentified human remains (UHRs) of five males recovered from the water near the southwestern coast of Sardinia by the Italian Harbor Master's Office. Nail clippings provided an optimal source of autologous DNA for molecular identification in a very short time, producing complete autosomal and Y-STR profiles even under conditions of high body degradation. Unfortunately, no match neither compatibility occurred using autosomal STRs (aSTRs), initially. Upon analyzing the Y-haplotypes, we found out they had already been observed in northern Africa, providing us important investigative leads. This prompted the International Criminal Police Organization (INTERPOL) to provide us with references of alleged relatives that were then confirmed to be related. The use of fingernails represents an excellent DNA source especially for genetic identification of decomposed bodies recovered in seawater environment. Notably, DNA extracted from nails gave high-quality Y-STR haplotypes by which predicting paternal ancestry of the unidentified donors may result fundamental in the forensic investigative context.

Extended families? Contact expectations and experiences of egg donors donating to previously unknown recipients

In New Zealand egg donation is identity-release, and donors may be known to recipients, e.g. family members/friends, or previously unknown e.g. clinic-recruited or sourced through advertising. In the case of unknown donors, New Zealand practice allows donors and recipients to meet face-to-face prior to donation in a joint counselling meeting. While contact details may not necessarily be exchanged in counselling, information-exchange and contact expectations are usually addressed. In previous papers, we explored donors’ motivations and experiences of donation. In this paper, we explore donors’ ideas around their role in relation to the donor-conceived person (DCP) and their expectations and experiences of information-exchange and contact. While donors did not see themselves as parents and were aware of appropriate boundaries, they described a sense of ongoing connection to DCP, often framing this in extended family terms. They desired to be kept informed about DCP, considered themselves ‘on standby’ for information requests or in-person contact and valued the opportunity for connection between their children and DCP. Donors were, however, cognisant of the limits to their ability to ensure information-exchange and contact and sometimes struggled with their perceived disempowered position. Meeting prior to donation may both clarify and reinforce expectations of information-exchange and contact.

O40 Technology advancement in getting donor HLA information from recipient with unknown donor typing

O40 Technology advancement in getting donor HLA information from recipient with unknown donor typing

Natural Recombination among Type I Restriction-Modification Systems Creates Diverse Genomic Methylation Patterns among Xylella fastidiosa Strains.

Xylella fastidiosa is an important bacterial plant pathogen causing high-consequence diseases in agricultural crops around the world. Although as a species X. fastidiosa can infect many host plants, there is significant variability between strains regarding virulence on specific host plant species and other traits. Natural competence and horizontal gene transfer are believed to occur frequently in X. fastidiosa and likely influence the evolution of this pathogen. However, some X. fastidiosa strains are difficult to manipulate genetically using standard transformation techniques. Several type I restriction-modification (R-M) systems are encoded in the X. fastidiosa genome, which may influence horizontal gene transfer and recombination. Type I R-M systems themselves may undergo recombination, exchanging target recognition domains (TRDs) between specificity subunits (hsdS) to generate novel alleles with new target specificities. In this study, several conserved type I R-M systems were compared across 129 X. fastidiosa genome assemblies representing all known subspecies and 32 sequence types. Forty-four unique TRDs were identified among 50 hsdS alleles, which are arrayed in 31 allele profiles that are generally conserved within a monophyletic cluster of strains. Inactivating mutations were identified in type I R-M systems of specific strains, showing heterogeneity in the complements of functional type I R-M systems across X. fastidiosa. Genomic DNA methylation patterns were characterized in 20 X. fastidiosa strains and associated with type I R-M system allele profiles. Overall, these data suggest hsdS genes recombine among Xylella strains and/or unknown donors, and the resulting TRD reassortment establishes differential epigenetic modifications across Xylella lineages. IMPORTANCE Economic impacts on agricultural production due to X. fastidiosa have been severe in the Americas, Europe, and parts of Asia. Despite a long history of research on this pathogen, certain fundamental questions regarding the biology, pathogenicity, and evolution of X. fastidiosa have still not been answered. Wide-scale whole-genome sequencing has begun to provide more insight into X. fastidiosa genetic diversity and horizontal gene transfer, but the mechanics of genomic recombination in natural settings and the extent to which this directly influences bacterial phenotypes such as plant host range are not well understood. Genome methylation is an important factor in horizontal gene transfer and bacterial recombination that has not been comprehensively studied in X. fastidiosa. This study characterizes methylation associated with type I restriction-modification systems across a wide range of X. fastidiosa strains and lays the groundwork for a better understanding of X. fastidiosa biology and evolution through epigenetics.

Different RNA Elements Control Viral Protein Synthesis in Polerovirus Isolates Evolved in Separate Geographical Regions.

Most plant viruses lack the 5′-cap and 3′-poly(A) structures, which are common in their host mRNAs, and are crucial for translation initiation. Thus, alternative translation initiation mechanisms were identified for viral mRNAs, one of these being controlled by an RNA element in their 3′-ends that is able to enhance mRNA cap-independent translation (3′-CITE). The 3′-CITEs are modular and transferable RNA elements. In the case of poleroviruses, the mechanism of translation initiation of their RNAs in the host cell is still unclear; thus, it was studied for one of its members, cucurbit aphid-borne yellows virus (CABYV). We determined that efficient CABYV RNA translation requires the presence of a 3′-CITE in its 3′-UTR. We showed that this 3′-CITE requires the presence of the 5′-UTR in cis for its eIF4E-independent activity. Efficient virus multiplication depended on 3′-CITE activity. In CABYV isolates belonging to the three phylogenetic groups identified so far, the 3′-CITEs differ, and recombination prediction analyses suggest that these 3′-CITEs have been acquired through recombination with an unknown donor. Since these isolates have evolved in different geographical regions, this may suggest that their respective 3′-CITEs are possibly better adapted to each region. We propose that translation of other polerovirus genomes may also be 3′-CITE-dependent.

Development and Validation of MPS-Based System for Human Appearance Prediction in Challenging Forensic Samples.

Forensic DNA phenotyping (FDP) provides the ability to predict the human external traits from unknown sample donors, directly from minute amounts of DNA found at the crime scene. We developed a MPS multiplex assay, with the aim of genotyping all 41 DNA markers included in the HIrisPlex-S system for simultaneous prediction of eye, hair and skin colours. Forensic samples such as blood, skeletal remains, touch DNA, saliva swab, artificially degraded samples together with individuals with known phenotypes and a set of 2800 M control DNA were sequenced on the Ion Torrent platform in order to evaluate the concordance testing results and the forensic suitability of the 41-plex MPS assay. The panel was evaluated by testing a different number of PCR cycles and the volume of reagents for library preparation. The study demonstrated that full and reliable profiles were obtained with 0.1–5 ng, even with high degraded DNA. The increment of the number of PCR cycles results in an improvement of correctly genotyping and phenotyping for samples with low amounts of degraded DNA but higher frequencies of artefacts were found. The high DNA degradation level did not influence the correct genotyping and phenotyping and the critical parameter affecting the result is the quantity of input DNA. Eye and hair colour was predicted in 92.60% of individuals and skin colour in 85.15% of individuals. The results suggest that this MPS assay is robust, highly sensitive and useful for human pigmentation prediction in the forensic genetic field.

Calpains in cyanobacteria and the origin of calpains

Calpains are cysteine proteases involved in many cellular processes. They are an ancient and large superfamily of enzymes responsible for the cleavage and irreversible modification of a large variety of substrates. They have been intensively studied in humans and other mammals, but information about calpains in bacteria is scarce. Calpains have not been found among Archaea to date. In this study, we have investigated the presence of calpains in selected cyanobacterial species using in silico analyses. We show that calpains defined by possessing CysPC core domain are present in cyanobacterial genera Anabaena, Aphanizomenon, Calothrix, Chamaesiphon, Fischerella, Microcystis, Scytonema and Trichormus. Based on in silico protein interaction analysis, we have predicted putative interaction partners for identified cyanobacterial calpains. The phylogenetic analysis including cyanobacterial, other bacterial and eukaryotic calpains divided bacterial and eukaryotic calpains into two separate monophyletic clusters. We propose two possible evolutionary scenarios to explain this tree topology: (1) the eukaryotic ancestor or an archaeal ancestor of eukaryotes obtained calpain gene from an unknown bacterial donor, or alternatively (2) calpain gene had been already present in the last common universal ancestor and subsequently lost by the ancestor of Archaea, but retained by the ancestor of Bacteria and by the ancestor of Eukarya. Both scenarios would require multiple independent losses of calpain genes in various bacteria and eukaryotes.

Evaluating the Impact of Dropout and Genotyping Error on SNP-Based Kinship Analysis With Forensic Samples.

Technological advances in sequencing and single nucleotide polymorphism (SNP) genotyping microarray technology have facilitated advances in forensic analysis beyond short tandem repeat (STR) profiling, enabling the identification of unknown DNA samples and distant relationships. Forensic genetic genealogy (FGG) has facilitated the identification of distant relatives of both unidentified remains and unknown donors of crime scene DNA, invigorating the use of biological samples to resolve open cases. Forensic samples are often degraded or contain only trace amounts of DNA. In this study, the accuracy of genome-wide relatedness methods and identity by descent (IBD) segment approaches was evaluated in the presence of challenges commonly encountered with forensic data: missing data and genotyping error. Pedigree whole-genome simulations were used to estimate the genotypes of thousands of individuals with known relationships using multiple populations with different biogeographic ancestral origins. Simulations were also performed with varying error rates and types. Using these data, the performance of different methods for quantifying relatedness was benchmarked across these scenarios. When the genotyping error was low (<1%), IBD segment methods outperformed genome-wide relatedness methods for close relationships and are more accurate at distant relationship inference. However, with an increasing genotyping error (1–5%), methods that do not rely on IBD segment detection are more robust and outperform IBD segment methods. The reduced call rate had little impact on either class of methods. These results have implications for the use of dense SNP data in forensic genomics for distant kinship analysis and FGG, especially when the sample quality is low.

P-768 Families' experience of insemination fraud : a qualitative study

Abstract Study question What is the experience of parents and their offspring when they discover they were victims of insemination fraud, i.e. a voluntary substitution of sperm samples? Summary answer Participants reported experiencing shock, sideration and disbelief, feelings of being betrayed by the medical institution, and concerns about the repercussions on family bonds. What is known already Despite growing concerns about third-party assisted human reproduction, several loopholes remain in the legislation governing sperm donation. For example, the lack of consistency across clinics in donation tracking and record-keeping procedures has led to cases of accidental or voluntary substitution of sperm donations. Such substitutions imply that the sperm of the donor selected by the parents or that of the father of the child is not the sperm used for conception. With the advent of DNA kits, more and more cases of substitution are being uncovered. However, this phenomenon has not received the scientific attention it deserves. Study design, size, duration This is an exploratory study using a qualitative methodology. Data collection was conducted in Canada in the winter of 2019 and spring of 2021 using a purposive sampling method. Participants/materials, setting, methods In total, 13 people made up our sample: seven parents (two fathers and five mothers) and six donor-conceived people conceived (four teenagers, aged between 13 and 16 years and two adults aged 38 and 39 years). Donor conception was used in the context of male infertility (N = 1), vasectomy (N = 3), sperm freezing after cancer (N = 1), and celibacy (N = 1). The data was collected using semi-structured individual interviews. Main results and the role of chance A thematic analysis shows that the experience varies according to one’s position in the insemination process (whether one uses it or is the product of it), to the nature of the substitution and to the suspicions one has (or not) prior to the discovery. However, all the participants described the announcement of the substitution as a shock that strongly undermines trust in the assisted reproduction industry. In cases where the father’s sperm was substituted, this leads to having to renounce biological paternity and the ideal of a child born to both parents. In cases where the chosen donor was substituted, this forces the parents and their offspring to give up (temporarily or permanently) the possibility of tracing the man who conceived the child and/or the donor siblings. The substitution generates then for the parents a feeling of worry about the medical and psychological repercussions for their child and, for the children, a feeling of incomplete identity. On the other hand, in cases where the doctor’s sperm was substituted for that of an unknown donor, the persons conceived by donation seemed to have a better reaction because it provided them with answers as to their origins. Limitations, reasons for caution Despite the innovative nature of the study, the size of the sample and the variability of the experiences do not allow for definitive conclusions to be drawn about this phenomenon and limit the understanding that can be gained from it to this particular fraud, emanating from the same doctor. Wider implications of the findings With the democratization of DNA testing, this type of phenomenon could become more widespread. It is therefore important to document it to better understand its consequences on the disintegration of the filial or family bond, the possibility of redefining the biological family, and the redefinition of the original parental project. Trial registration number N/A

Comparative genomic analysis of Thermus provides insights into the evolutionary history of an incomplete denitrification pathway.

Biological denitrification is a crucial process in the nitrogen biogeochemical cycle, and Thermus has been reported to be a significant heterotrophic denitrifier in terrestrial geothermal environments. However, neither the denitrification potential nor the evolutionary history of denitrification genes in the genus Thermus or phylum Deinococcota is well understood. Here, we performed a comparative analysis of 23 Thermus genomes and identified denitrification genes in 15 Thermusstrains. We confirmed that Thermus harbors an incomplete denitrification pathway asnone of the strains contain the nosZ gene. Ancestral character state reconstructions and phylogenetic analyses showed that narG, nirS, and norB genes were acquired by the last common ancestor of Thermales and were inherited vertically. In contrast, nirK of Thermales was acquired via two distinct horizontal gene transfers from Proteobacteria to the genus Caldithermus and from an unknown donor to the common ancestor of all known Thermus species except Thermus filiformis. This study expands our understanding of the genomic potential for incomplete denitrification in Thermus, revealinga largely vertical evolutionary history of the denitrification pathway in the Thermaceae, and supportingthe important role for Thermus as an important heterotrophic denitrifier in geothermal environments.

Microhaplotype and Y-SNP/STR (MY): A novel MPS-based system for genotype pattern recognition in two-person DNA mixtures

BackgroundsY-chromosomal haplotypes based on Y-short tandem repeats (STRs) and Y-single nucleotide polymorphisms/insertion and deletion polymorphisms (SNPs/InDels) are used to characterize paternal lineages of unknown male trace donors. However, Y-chromosomal genetic markers are not currently sufficient for precise individual identification. Microhaplotype (MH), generally < 200 bp on autosomes and consisting of two or more SNPs, was recently introduced in forensic genetics with the development of massive parallel sequencing technology and may facilitate identification and DNA mixture deconvolution. Therefore, combining the two kinds of genetic markers may be beneficial in many forensic scenarios, especially crime scenes with male suspects, such as sexual assault cases. MethodsIn the present study, we developed a novel MPS-based panel, Microhaplotype and Y-SNP/STR (MY), by multiplex PCR and 150-bp paired-end sequencing, including 114 Y-SNPs (twelve dominant Y-DNA haplogroups), 45 Y-STRs (N-1 stutter < 0.09; estimated mutation rate < 5 × 10−3), and 22 MHs (allele coverage ratio > 0.91; pairwise distance > 10 Mb). Additionally, MY system-based genotype pattern recognition (GPR), a regression-based method to identify the genotype pattern for each MH locus, is proposed for two-person DNA mixture deconvolution. We integrated 26 two-person genotype combinations into nine genotype patterns and validated the application range of GPR based on DNA profiles of ten sets of simulated male-male DNA mixtures (1:10–1:2). ResultsThe effective number of alleles (Ae) ranged from 3.62 to 14.72, with an average of 7.17, in 100 Chinese Guangdong Han individuals. The cumulative discrimination power was 1–5.00 × 10−31, and the cumulative power of exclusion was 1–5.00 × 10−8 and 1–4.85 × 10−12 for duo and trio paternity testing, respectively. Furthermore, the actual mixing ratio-depth of coverage (DoC) ratio (RDoC) regression relationships were established for different genetic markers and genotype patterns. In five overlapping areas, genotype differentiation of the major and minor contributors required likelihood ratio methods. In nonoverlapping areas, the genotype pattern could be recognized by comparing the observed RDoC and RDoC ranges. ConclusionThe GPR can be used to deconvolute two-person DNA mixtures (application range: 1:10–1:2) for individual identification.

Specificity and modularity of flagellin nonulosonic acid glycosyltransferases.

Many bacterial flagella are specifically O-glycosylated with nonulosonic acids, including the sialic acid derivatives, pseudaminic acid or legionaminic acid. Unlike protein glycosyltransferases that are extracytoplasmic, flagellin glycosyltransferases (fGTs) act cytoplasmically with unknown donor or acceptor specificities. The recent reconstitution of fGT-based glycosylation in heterologous hosts enables analyses underpinning such specificity.

Assessment of the level of willingness to donate liver and kidney among the general population in Saudi Arabia

Background: For patients with end-stage liver disease and underlying chronic kidney disease or prolonged acute kidney injury, liver and kidney transplantation is a life-saving procedure. As a result, estimating the general population’s willingness to donate liver and kidney is critical. Objectives: To assess the level of willingness to donate liver and kidney and its relationship with different socio demographic factors among the general population in Saudi Arabia. Methods: This is cross sectional study that was conducted in various regions in Saudi Arabia during March – May 2022. Data were collected through online self-administered questionnaire prepared via Google Form. Participants were selected using a convenient non-probability sampling technique. SPSS was used to perform data analysis. Results: A total of 983 participants were included in this study. The majority were females. The most common age group was 18-30 years. Our results found that 23.6 % of the participants reported their willingness to donate a liver or a kidney for an unknown patient, whereas 71.1% reported willingness to do so for a close family member or a friend. 58.3% were willing to accept a donated liver or kidney from an unknown donor whereas 67.7% were willing to accept it from a close family member or a friend. Moreover, gender was significantly associated with willingness of donation for an unknown patient (P&lt;0.05) whereas gender was not significantly associated with willingness for donation for a close family member or a friend. Age groups, marital status and occupational status was found to be significantly associated with donation for both unknown patients and close family members or friends (P&lt;0.05). Conclusion: According to our findings, the willingness of participants to donate a kidney or a liver was 23.6 percent for unknown patients and 71.1 percent for close relatives. Gender, marital status, age, income and occupation were observed to be significantly associated with willingness to donate an organ for unknown patients or close family members or friends or both. Key words: donation, liver, kidney, general population, Saudi Arabia

Genetic differentiation of Xylella fastidiosa following the introduction into Taiwan.

The economically important plant pathogen Xylella fastidiosa has been reported in multiple regions of the globe during the last two decades, threatening a growing list of plants. Particularly, X. fastidiosa subspecies fastidiosa causes Pierce’s disease (PD) of grapevines, which is a problem in the USA, Spain, and Taiwan. In this work, we studied PD-causing subsp. fastidiosa populations and compared the genome sequences of 33 isolates found in Central Taiwan with 171 isolates from the USA and two from Spain. Phylogenetic relationships, haplotype networks, and genetic diversity analyses confirmed that subsp. fastidiosa was recently introduced into Taiwan from the Southeast USA (i.e. the PD-I lineage). Recent core-genome recombination events were detected among introduced subsp. fastidiosa isolates in Taiwan and contributed to the development of genetic diversity. The genetic diversity observed includes contributions through recombination from unknown donors, suggesting that higher genetic diversity exists in the region. Nevertheless, no recombination event was detected between X. fastidiosa subsp. fastidiosa and the endemic sister species Xylella taiwanensis , which is the causative agent of pear leaf scorch disease. In summary, this study improved our understanding of the genetic diversity of an important plant pathogenic bacterium after its invasion to a new region.

Frequency of rare, serious donor reactions: International perspective.

Severe blood donor adverse events are rare, but due to their rarity studying them can be difficult. To get an accurate estimate of their frequency and rate in the donor population it may be necessary to combine donation data across countries. International blood collection organizations (BCOs) provided data on rare/severe donor reactions as well as denominator information for their donor populations from 2015 to 2017. Donor reactions were classified using standardized definitions. BCOs from six countries provided reaction data for more than 22 million donations. A total of 480 rare reactions were reported of which 76.7% were imputed as definite and 11% probable. Rates of rare reactions were higher in females and first-time donors. Systemic rare reactions were the most common reaction type, accounting for over three quarters of reactions reported. Of systemic reactions, vasovagal reactions with loss of consciousness and injury or off-site (n=350) made up the majority and occurred 1.53 per 100,000 donations. For the 22.3% that were localized reactions, the majority of these were cellulitis (n=71, 0.31 per 100,000 donations) followed by deep venous thrombosis (n=21, 0.09 per 100,000 donations). Pulling together data from multiple BCOs across countries allows for a better understanding of rare reactions, such as vasovagal reaction with injury or cellulitis, and for generating a reliable incidence rate for air embolism or compartment syndrome. However, gaps remain due to missing elements such as unknown donor status or location of reaction.