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Study question What is the relevance to offer panels of infertility genes as a diagnostic tool for infertile patients? Summary answer Our results demonstrate the interest of custom designed panel to define the genetic etiology of infertile couple in up to 26% of cases. What is known already The etiology of infertility is very heterogeneous, and due to the complexity of the reproductive process, standard fertility examinations fail to identify an etiology in 15 to 30% of infertile couples. It is believed that about half of these cases could be explained by a genetic defect. Until recently, routine genetic tests in the field of infertility were restricted to karyotyping, Yq microdeletion, CFTR mutation screening and FMR1 gene screening. The improvement of high throughput sequencing (HTS) technologies has considerably modified the discovery of the genetic causes of diseases allowing the development of new genetic diagnostic tools. Study design, size, duration Since 2016, we have set up, within the genetic diagnostic service of the Strasbourg University Hospital (HUS), a gene panel assay of preselected genes for the genetic diagnosis of male and female non-syndromic infertility. Since 2016, reflecting the high level of the research in this field, we have upgraded our panel two times. Initially, our panel included 16 infertility genes, then 51. We are now offering a panel of 133 infertility genes. Participants/materials, setting, methods Three different infertility gene panels were used to analyse 205 infertile cases; 62 females and 143 males. Agilent-SureSelectQXT Target Enrichment system was used to prepare libraries from genomic DNA. Sequencing was performed on Illumina NextSeq 550 with 2x150bp reads. Variant analysis was achieved using VaRank tool. One control DNA with known genotype was used in the first run of each design for the quality control. Identity of each patient was confirmed by independent Taqman technology. Main results and the role of chance Our first custom designed infertility panel (V1) contained 16 genes; one female and 11 male samples were tested, one positive male sample was identified and resulted in a diagnostic yield of 8.3% (1/12). The second version of the panel (V2), encompassed 51 genes, 22 female and 91 male samples were analysed, allowing a diagnostic yield of 6.1% [7/113; diagnostic rate for female was 9% (2/22), diagnostic rate for male was 5.5% (5/91)]. The third version of our panel (V3) contains 133 infertility genes and so far the diagnostic yield is 26.3% (21/80). Among 80 samples analysed, 39 of them were female for whom we got a diagnostic rate of 17.9% (7/39) and 41 were male for whom we got a diagnostic rate of 34.1% (14/41). Concerning V2 panel, we analysed 69 azoospermic patients for whom the diagnosis was only based on semen analysis and we identified only 2 pathogenic variants (2.8%, 2/69). For the V3 panel, the analysis of 30 azoospermic samples among which 26 diagnosed via testicular biopsy and pathology report, leaded to a diagnostic yield of 33.3% (10/30). These results underline the importance of well-defined clinical data in the field of genetics of infertility. Limitations, reasons for caution The main limitation is the number of patients’ analysed so far. In order to fully challenge the clinical interest of such diagnostic tool, a larger group of patients needs to be analysed. Wider implications of the findings The precise molecular diagnostic is important for adapting the best treatment and counsel not only to patients but to their spouse and relatives. This study allows us to decipher the prevalence of mutations in identified genes for a specific infertility phenotype on our cohort of infertile patients. Trial registration number not applicable

Presymptomatic testing for Huntington disease has been available for 15 years. The possibility of determining the genetic status of an at-risk person for the disorder which runs in his or her family raises questions because of the absence of preventive treatments. In addition, being carrier does not allow to determine when the disease starts and how it will evolve, impairing the possibilities of planning the future. A pluridisciplinary approach to predictive testing with care before, during and after the test taking into account the medical, social and psychological aspects of the disease is good practice. At the present time, only a minority of at-risk individuals request presymptomatic testing and almost 50% do not pursue until the results. The consequences of the test may be harmful, more frequently after an unfavorable than after a favorable result. Motivations and the outcome in terms of request for prenatal testing after a carrier result are known today and the number or prenatal testing remains very limited. Preimplantation genetic testing is an alternative for couples who knows or do not their own genetic status. We report our experience in two French centres: Paris for presymptomatic and prenatal testing and Strasbourg for preimplantation diagnosis.

Resume Objectif Le but de ce travail est d'exposer la situation du don et de l'accueil d'embryons en France et dans le monde, d'en presenter les difficultes pratiques ainsi que les resultats obtenus dans notre centre trois ans apres la mise en place de cette procedure. Patients et methodes Les modalites de mise en œuvre sont regies en France par plusieurs textes legislatifs parus entre 1999 et 2004. Apres avoir contacte les couples disposant d'embryons surnumeraires congeles dans notre centre depuis au moins deux ans, les consultations obligatoires avec les couples souhaitant faire don de leurs embryons a un autre couple ont ete mises en place. Les couples receveurs ont beneficie d'une prise en charge pluridisciplinaire permettant d'evaluer l'indication d'accueil d'embryons. Resultats Parmi les couples contactes, 16,7 % optent pour le don d'embryon mais moins de la moitie d'entre eux finalise cette decision (6 % des couples ayant des embryons congeles). Les indications medicales principales retenues pour l'accueil d'embryons sont la double sterilite, les indications genetiques non etiquetees, les echecs d'AMP (pauci fecondation ou mauvaise qualite embryonnaire) et les couples candidats au don d'ovocytes pour qui l'attente parait trop longue. Un taux de grossesse de 28,6 % a ete obtenu apres 21 premiers transferts d'embryons. Discussion et conclusion Les resultats de l'accueil d'embryons en France confirment l'experience internationale tant au niveau de la penurie en embryons donnes qu'en terme d'indications et de resultats. Meme si la legitimite de l'accueil d'embryons est indeniable, certaines questions restent en suspens notamment sur le plan ethique et necessitent une reflexion nationale.

Despite excellent published results, the lack of well-designed, multicentre, randomized clinical trials results in an absence of general consensus on the efficacy of autologous endometrial cells coculture (AECC) in Assisted Reproductive Technology (ART). An open, multicentre, prospective, randomized controlled trial was designed to compare the pregnancy rate (PR) after the transfer of one blastocyst on day 5 after AECC to the transfer of one embryo on day 3 (control group). Patients were women aged 18 to 36, undergoing an ART cycle with no more than 1 embryo transfer failure. Sample size was calculated at 720 for a superiority trial involving an intermediate analysis at 300 patients. We present the results of the intermediate analysis that resulted in the study ending considering the observed difference. Three hundred thirty nine patients were randomized: 170 in the AECC group and 169 in the control group. The clinical PR per transfer was 53.4% with AECC and 37.3% in the control group (p=0.025). The quality of embryos was improved with AECC. These results suggest that implementation of the AECC technique to a large number of In-Vitro Fertilization (IVF) centres could lead to a substantial improvement in the proportion of successful assisted reproduction. The study was supported by the Laboratoires Genévrier, France.

Resume Objectif. – Evaluer l’efficacite de notre prise en charge des infections cervicovaginales des couples inclus en assistance medicale a la procreation (AMP). Patients et methodes. – Durant l’annee 2000, un prelevement cervico-vaginal et une spermoculture ont ete realises dans le mois precedant la ponction ovocytaire chez 951 couples. Un traitement antibiotique adapte a l’antibiogramme a ete prescrit en cas d’infection. Resultats. – Pour 733 patientes le prelevement cervicovaginal ne revelait pas d’infection (77,1 %), 222 ont concu (30,29 % grossesse/transfert). Une infection a ete retrouvee au niveau cervicovaginal et traitee dans 218 cas pour lesquels un taux de grossesse comparable a ete observe (30,27 %). Le taux d’implantation embryonnaire est neanmoins significativement abaisse en cas d’infection du prelevement : 14,6 vs 19,3 % (p Discussion et conclusion. – La presence d’une infection au niveau cervicovaginal, meme traitee, semble affecter l’implantation embryonnaire. L’infection concomitante du conjoint exacerbe cet effet deletere. Le report de la tentative parait alors la solution la plus respectueuse des interets du couple infertile.

Resume Objectifs – La mucoviscidose est une maladie autosomique recessive frequente dont le majorite des cas est causee par une deletion (ΔF508) dans le gene CFTR. C’est l’indication la plus frequente de diagnostic preimplantatoire, technique qui permet d’analyser des embryons obtenus par fecondation in vitro et de ne transferer que des embryons sains dans l’uterus de la patiente. Patients et methode – Nous presentons le premier diagnostic preimplantatoire du centre de Strasbourg realise chez un couple presentant une sterilite due a une agenesie bilaterale des canaux deferents et a risque d’avoir un enfant atteint de mucoviscidose severe par mutation homozygote ΔF508. L’injection intra cytoplasmique de sperme testiculaire a permis d’obtenir des embryons qui ont ete biopsies et analyses trois jours apres fecondation. L’amplification par PCR du fragment contenant le locus ΔF508 du gene de la mucoviscidose a permis de mettre en evidence la mutation ΔF508 et de ne transferer que des embryons sains. Resultats – Ce cycle de diagnostic preimplantatoire a permis le transfert de trois embryons. Une grossesse gemellaire a ete obtenue et les deux enfants issus de cette grossesse sont indemnes de la mutation en cause. Conclusions – Le diagnostic preimplantatoire de la mucoviscidose par detection de la mutation ΔF508 est disponible dans notre centre. Dans cette observation, nous avons pu prendre en charge a la fois le probleme de sterilite et le risque de transmettre une mucoviscidose severe. Le diagnostic peimplantatoire est egalement applicable pour d’autres mutations du gene de la mucoviscidose et pour d’autres pathologies.

The H19 gene is subject to genomic imprinting because it is methylated and repressed after paternal inheritance and is unmethylated and expressed after maternal inheritance. We recently identified a 1.1-kb control element in the upstream region of the H19 gene that functions as a cis - acting silencer element in Drosophila . Here we investigate the function of this element in mice. We demonstrate that both H19–lacZ and H19–PLAP reporter transgenes can undergo imprinting with repression and hypermethylation after paternal transmission at many integration sites. However, transgenes that were deleted for the 1.1-kb silencer element showed loss of paternal repression, but they did not show marked changes in the paternal methylation of the remaining upstream region. This study demonstrates that the 1.1-kb control element identified in Drosophila is required to silence paternally transmitted H19 minitransgenes in mice.

We previously identified Peg1/Mest as a novel paternally expressed gene in the developing mouse embryo. The human PEG1 gene was recently assigned to 7q32 and shown to be imprinted and paternally expressed. Therefore, PEG1 deficiency could participate in the aetiology of pre- and post-natal growth retardation associated with maternal uniparental disomy 7 in humans. We have now initiated the characterization of the Peg1 locus in order to identify and dissect cis-acting elements implicated in its imprinted monoallelic expression. The genomic structure of Peg1 as well as the DNA sequence of the 5'-end of the gene, including 2.4 kb of promoter sequences and covering the first 2 exons, have been determined. Important sequence elements, such as a CpG island spanning exon 1 and direct repeats, are identified and discussed. To address the role of epigenetic modifications in the imprinting of Peg1, a methylation analysis of the Peg1 gene is presented. Partially methylated cytosine residues in 13.5 d.p.c. embryos and undifferentiated ES cells were identified. Using embryos carrying a targetted mutation at the Peg1 locus, we show that this partial promoter methylation pattern reflects a strict parent-of-origin-specific differential methylation: the expressed paternal allele is unmethylated, whereas the silenced maternal allele is fully methylated at the CpG sites studied. That the gametes carry the epigenetic information necessary to lay down this allele-specific methylation pattern is suggested by analysis of DNA isolated from sperm and parthenogenetic embryos.

Genomic imprinting is an epigenetic marking process that confers parent-of-origin-dependent expression on certain genes. These imprinted genes are sometimes found in clusters, suggesting a possible involvement of higher order regulatory elements controlling expression and imprinting of genes organised in such clusters. In the distal chromosome 7 there are at least four imprinted genes: Mash2, Ins2, Igf2 and H19. Recent evidence(1) suggests that imprinting and expression of at least Igf2 and H19 may be mechanistically linked.

To accurately delineate the DNA sequence elements involved in the transcriptional regulation of the murine MHC class II gene E alpha, we have constructed a set of "linker-scanning" mutants of the E alpha promoter region. These were made by the gapped heteroduplex technique and result in a set of 10-bp replacement mutations, covering the -206 to -6 stretch of the promoter. The effect of these mutations on transcriptional activity was evaluated in several systems, either by transfection into cultured cells or by in vitro transcription. The data points to the now classical X and Y boxes as the most important control elements, either for constitutive expression in B lymphoma cells, or for IFN-gamma-inducible expression in macrophages. Motifs upstream of the X box also play a role, but are somewhat less critical. Overall, we find no marked difference between regulatory strategies in B lymphomas or activated macrophages.

Presymptomatic testing for Huntington disease has been available for 15 years. The possibility of determining the genetic status of an at-risk person for the disorder which runs in his or her family raises questions because of the absence of preventive treatments. In addition, being carrier does not allow to determine when the disease starts and how it will evolve, impairing the possibilities of planning the future. A pluridisciplinary approach to predictive testing with care before, during and after the test taking into account the medical, social and psychological aspects of the disease is good practice. At the present time, only a minority of at-risk individuals request presymptomatic testing and almost 50% do not pursue until the results. The consequences of the test may be harmful, more frequently after an unfavorable than after a favorable result. Motivations and the outcome in terms of request for prenatal testing after a carrier result are known today and the number or prenatal testing remains very limited. Preimplantation genetic testing is an alternative for couples who knows or do not their own genetic status. We report our experience in two French centres: Paris for presymptomatic and prenatal testing and Strasbourg for preimplantation diagnosis.

The aim of this study was to present the situation of embryo donation in France and around the world, to expound the difficulties of its practice and the results obtained in our centre 3 years after the introduction of this procedure.Embryo donation in France is controlled by implemented decrees published between 1999 and 2004. The couples, who have stored frozen embryos since at least two years, were contacted for a pluridisciplinary medical consultation. The indication of embryo donation was evaluated for the recipients through a pluridisciplinary approach.Among the interviewed couples, 16.7% have chosen embryo donation but only half of them have completed the procedure (6% of the couples with frozen embryos). The main indications for embryo donation were a double sterility, unexplained genetic disease, ART failures (poor fertilization or bad embryo quality) and oocyte donation when the delay was too long for the couples. The pregnancy rate was 28.6% after the 21 first embryo transfers.The results of embryo donation confirm the international experience both considering the poor number of donated embryos, medical indications and results. Embryo donation has its place among ART techniques, but one should not ignore the general debate on ethical questions raised by this procedure.

International audience; Teratozoospermia is characterized by the presence of spermatozoa with abnormal morphology in sperm. This condition is frequently associated with infertility and intracytoplasmic sperm injection (ICSI) is frequently used as the treatment of choice. However, the use of ICSI has created consequential debate concerning the genetic risk for the offspring. Fluorescence in situ hybridization technique (FISH), allowing the specific identification of human chromosomes in sperm nuclei, has been used to study chromosome abnormalities in sperm from men with teratozoospermia and a normal karyotype. In this review, we present studies that have tried to determine if men with a normal blood karyotype but suffering from teratozoospermia present a higher aneuploidy frequency. The literature is limited to three forms of teratozoospermia. The first group consists of "polymorphic teratozoospermia", where a majority of spermatozoa display more than one type of abnormality. In this case, only a slight increase in aneuploidy frequency is observed, which cannot be differentiated from the results observed in oligo-astheno-teratozoospermia (OAT). The second group, named "globozoospermia", is characterized by round spermatic heads, absence of acrosome and disorganization of mid-piece and tail. In this case, some studies have shown a significant, but moderate, increase in the aneuploidy frequency for acrocentrics and sex chromosomes. The aneuploidy frequency remains low, also ICSI can be proposed to these patients, but few successes occur. The third group consists of "enlarged head teratozoospermia", where almost all spermatozoa have an enlarged head, multiple tail and abnormal acrosome. In this case a very high level of missegregation is observed, leading to nearly 100% aneuploidy. In this particular group, ICSI must be refuted, and patients have to be redirected to other possibilities, like sperm donation.

Preimplantation genetic diagnosis (PGD) is an alternative to prenatal diagnosis allowing the detection of genetic diseases on IVF embryos before their transfer into the uterus and before the pregnancy. The aim of this procedure is to obtain unaffected or carrier embryos in order to avoid the burden of termination of pregnancy after prenatal diagnosis for couples at risk of transmitting particularly severe genetic disorders to their offspring. For monogenic diseases, PGD is most often based on single blastomere amplification by polymerase chain reaction (PCR). More than a decade after the first births, the possibilities of diagnosis for monogenic diseases have considerably increased. As for molecular biology and conventional diagnosis, the technologies and strategies for PGD are continually improved, with for instance introduction of fluorescent PCR or multiplex amplification. In this review, we describe several approaches for PGD of monogenic diseases, followed by an overview of the French practice, particularly in our lab.

To evaluate the efficiency of our treatment of vaginal infection for couples included in an IVF program.Microbiologic screening of vaginal flora and semen has been performed one month prior to in vitro fertilization for 951 couples in 2000. Antibiotic treatment was prescribed in case of positive culture.Positive microbial growths were observed from endocervical and vaginal cultures in 218 women (22.9%). The clinical pregnancy rate was 30.29% in the group of patients without growth and 30.27% in the group with positive microbial growth. The implantation rate was significantly diminished in case of bacterial growth: 14.6 compared to 19.3% (P0.02) for sterile endocervical culture. Five main bacterial species were found at the cervical level: Candida albicans (69 cases), Ureaplasma urealyticum (49 cases), Gardnerella vaginalis (43 cases), Streptococcus B or D (24 cases) and Escherichia coli (22 cases). Positive cultures from both vagina and semen were observed for 77 couples whose clinical pregnancy rate was 19.5 vs 36.2% in case of vaginal infection alone (P0.01) with a spontaneous miscarriage rate of 46.7 compared to 17.6% (P0.01).Endocervical microorganisms, even treated with adapted antibiotics, may affect embryonic implantation. Positive culture from both female and male partner may enhance this negative effect. In this case, the best strategy would be to cancel the IVF treatment.

Preimplantation genetic diagnosis (PGD) requires the combined efforts of geneticists and workers in the field of reproductive medicine. This was studied on the basis of a questionnaire, sent to 35 members of the PGD Consortium of the European Society of Human Reproduction and Embryology (ESHRE). A reply was obtained from 20 centres. They represent the majority of activities in the field of PGD in the world. It is obvious that many of the activities (in vitro fertilisation, embryo culture and biopsy) take place in IVF units while others (counselling and diagnosis) are the responsibility of genetic diagnostic centres. The distances between both units vary considerably. In all but one centre sex determination is offered. Aneuploidy screening is offered in 13 out of 20 centres. PGD of translocations and other structural chromosome abnormalities is offered in all but one centre. The number of monogenic diseases offered varies considerably. In comparison to prenatal diagnosis PGD is more expensive. The majority of these costs are due to the IVF or ICSI procedure. The charges for PGD vary between about 600 euro and 4000 euro. In 16 out of 20 centres the parents to be must sign an informed consent form.

Cystic fibrosis is a common autosomal recessive disease most often caused by a deletion (delta F508) in the CFTR gene. It is the most common indication for preimplantaion genetic diagnosis which allows genetic analysis of embryos obtained after in vitro fertilization and transfer of unaffected embryos into the patient's uterus.We report the first preimplantation genetic diagnosis performed in Strasbourg for a couple at risk of having a child affected by severe cystic fibrosis due to a homozygous delta F508 mutation. Three days after fertilisation, embryos obtained after intra-cytoplasmic testiculare sperm injection were biopsied and analysed. PCR amplification of the genomic fragment containing the delta F508 locus allowed detection of the delta F508 mutation and transfer only of the unaffected embryos.Three embryos were transferred after this preimplantation genetic diagnosis. A twin pregnancy was obtained and the babies born from this cycle are both exempt from the mutation.Preimplantation genetic diagnosis for the cystic fibrosis delta F508 mutation is now available in our centre. In this report, we could resolve both the problem of infertility and the risk of transmission of a severe form of cystic fibrosis. Preimplantation genetic diagnosis is also available for other mutations involved in cystic fibrosis and also for other genetic diseases.

We have developed a new allele-specific amplification method for the preimplantation genetic diagnosis (PGD) of spinal muscular atrophy (SMA; Werdnig-Hoffmann disease) from a single cell. This method is based on the detection of the deletion of exon 7 of the telomeric copy of the survival motor neurone (SMN(t)) gene. An oligonucleotide was designed to be specific to the SMN(t) nucleotidic sequence with exonic mismatch G (for SMN(t))--A (for SMN(c)) at its 3' end. This test produces reliable PCR products in 95% of single lymphoblasts (85/88) tested as well as in 16/16 blastomeres from normal controls. Specificity analysis showed that we were able to detect homozygous deletion of the SMN(t) gene in 99% of single lymphoblasts (103/104) from a SMA patient. No contamination was detected in 68 blanks tested. Multiple cell and DNA dilution analysis revealed that the test is accurate and specific up to 100 pg DNA and should thus also be suitable for PGD at the blastocyst stage. This rapid procedure requires a single round of fluorescent PCR and no restriction digestion, while previously described single cell methods include nested PCR followed by restriction enzyme digestion. Two PGD cycles for SMA using this procedure were performed in our centre.

In 1997, the ESHRE PGD Consortium was formed as part of the ESHRE Special Interest Group on Reproductive Genetics, in order to undertake a long-term study of the efficacy and clinical outcome of preimplantation genetic diagnosis (PGD). In December 1999, the first PGD Consortium report was published discussing referrals of 323 couples, 392 PGD cycles and 82 pregnancies and 79 children born. In the second round of data collection, contributing centres were asked to send in data from their PGD activities before January 1997, as well as from 1st October 1998 until 1st May 2000, in order to have as complete as possible an overview of PGD practices in these centres. A further 563 referrals were sent in as well as 926 PGD cycles, and data on 89 pregnancies (including seven pregnancies ongoing from the previous group) and 83 children were collected. This has led to a considerable amount of cumulative data being acquired: over a period of 7 years (the oldest PGD cycle reported dates from 1994), referral data on 886 couples, cycle data on 1318 PGD cycles and data on 163 pregnancies and 162 babies were collected. In all, these data are encouraging: they show first, that the practice of PGD is becoming more and more established, and an increasing number of different applications is emerging; and second, that collecting these data is worthwhile, as they will be a valuable source of information for all those involved, e.g. in counselling patients and interacting with governmental bodies.

Our purpose was to determine if the number of retrieved oocytes, oocyte maturity, morphology, and other embryological parameters are related to the outcome of treatment.This retrospective study on 438 IVF cycles analyzes the numbers of retrieved oocytes, fractured zona oocytes, germinal vesical-stage oocytes, normally and abnormally fertilized oocytes, pregnancy rate, age of female partner, ovarian stimulation protocol, day of hCG injection, and serum estradiol concentration.(1) Pregnancy rate increases with an increase in the number of retrieved oocytes, (2) a high incidence of fractured zona pellucida oocytes has a negative effect on fertilization rate but none on pregnancy rate, (3) a high incidence of immature oocytes is associated with improved fertilization and pregnancy rates, and (4) an inverse relationship between the presence of immature oocytes and oocytes with fractured zona pellucida is suggested.Precise oocyte assessment in IVF cycles provides informations useful for the analysis and improvement of ovarian stimulation protocols.

The first clinical application of preimplantation genetic diagnosis (PGD) was reported almost a decade ago. Since then, the range of genetic defects that can be detected at single cell level has increased dramatically. At the 13th Annual Meeting of ESHRE in Edinburgh in 1997, a PGD Consortium was formed to undertake the first systematic and long-term study of the efficacy and clinical outcome of PGD. We report here the first data collection covering the period of January 1997 to September 1998. Referral data on 323 couples have been collected for a variety of monogenic and chromosomal disorders, providing information about which patients, at risk for which genetic diseases, are interested in PGD. Data were collected on 392 PGD cycles, resulting in 302 embryo transfers and 66 clinical pregnancies. Because of the importance of follow-up of the children born after PGD, participating centres were asked to contribute data on the pregnancies achieved and the children born after PGD since the start of their PGD programme. Data on 82 pregnancies and 110 fetal sacs were collected, and information was available on 79 children. Finally, biopsy, fluorescence in-situ hybridization and polymerase chain reaction protocols were collected, clearly showing that no consensus exists on technical aspects such as which culture medium to use, and emphasizing the role the PGD Consortium could play in setting up guidelines for good laboratory practice. In conclusion, it is clear that the effort of gathering data on PGD cycles is worthwhile and will be continued in the future, preferably using electronic data collection.

To investigate the relative contribution of retinoic acid receptor (RAR)beta isoforms in conotruncal septation, RAR beta 1 and beta 3 were inactivated in the mouse. Mice lacking RAR beta 1 and beta 3 appear normal. Disruption of these isoforms in RAR alpha or RAR gamma null genetic backgrounds results in a high postpartum lethality. However, except for ocular defects found in RAR beta 1-3/RAR gamma compound mutants, the double null mutants display only abnormalities seen in single null mutants. This probably reflects a functional redundancy with other RARs, most notably with RAR beta 2 which is five- to sixfold more abundant than RAR beta 1 and beta 3 and whose domain of expression is largely overlapping. The conotruncal ridges form normally in retinoid X receptor (RXR)alpha/RAR beta compound mutants but fail to fuse, apparently as a result of excessive apoptosis of mesenchymal cells. Additionally, many cardiomyocytes in the conotruncal wall of these mutants appear necrotic. Although RAR beta 1 and beta 3 are expressed specifically in the conotruncal ridges, failure of fusion of these structures is not more frequent in RXR alpha/RAR beta 1-3 double null mutants than in RXR alpha single null mutants. Similarly, the disruption of the sole RAR beta 2 isoform in a RXR alpha null genetic background does not result in an increase of the frequency of conotruncal septum agenesis. However, this agenesis is fully penetrant in RXR alpha/RAR beta +/- mutants, which reflects distinct role of RXR alpha:RAR beta 1 (and beta 3) and RXR alpha:RAR beta 2 heterodimers in promoting the survival of conotruncal mesenchymal cells. Unexpectedly, we discovered that, in wild-type embryos, the conotruncal mesenchyme is a major site of morphogenetic cell death and that conotruncal myocytes are occasionally necrotic. Thus, excessive cell death in the conotruncus is a potential cause of ventricular septal defects in humans.

Treatment with an anti-IL-4 monoclonal antibody protected susceptible C57BL/6 mice against challenge with an avirulent strain of T. gondii. Antibody therapy with 100 micrograms on days 0 and 7 post infection resulted in 100% survival of C57/BL6 mice infected orally. Survival was dose-dependent. Treatment prolonged parasitaemia but did not alter tissue parasite load. Increased serum IgG2a and IFN-gamma levels, together with low levels of IgG1, in mice treated with anti-IL-4 or an isotype control, indicated a trend towards a predominant Th1 response in all survivors. The persistence of an IgE response after treatment suggests that endogenous IL-4 was only partly neutralized or that other factors can induce the production of IgE in murine toxoplasmosis.

Introduction L’infertilite est un probleme majeur de sante publique. L’origine est masculine dans 21 % cas, le diabete en etant une cause possible. Une serie de cas d’infertilite a ete colligee afin de decrire le type d’infertilite et l’efficacite des techniques de PMA en terme de recuperation de spermatozoides chez des hommes diabetiques. Patients et methodes Etude retrospective sur 20 hommes suivis pour infertilite au CECOS de Strasbourg entre 2006 et 2009 : recueil des donnees sur dossiers du CECOS. Resultats 11 (55 %) sont diabetiques de type 1 (DT1) et 8 (40 %) diabetiques de type 2 (DT2) avec un âge moyen de 38 et 45 ans et une anciennete du diabete de 18 et 5 ans en moyenne respectivement. Un patient presente un MODY 3. 2/8 des DT2 sont sous insuline. 1 homme sur 2 presente une infertilite primaire (7 DT1 et 3 DT2) et 1/2 une infertilite secondaire (4 DT1 et 5 DT2). 9 hommes, tous DT1, presentent une ejaculation retrograde et 3 (2 DT1 et 1 DT2) une anejaculation. Chez 6 hommes, tous DT1 avec ejaculation retrograde, une oligospermie severe au spermogramme empechant une conservation de spermatozoides, une recherche de spermatozoides a ete effectuee dans les urines. Pour 4/6, une conservation a pu alors etre faite et pour 2/6 une biopsie testiculaire a ete necessaire dont 1 pour azoopermie excretoire. Une dysfonction erectile est presente chez 6 patients (3 DT1 et 3 DT2). Conclusion Les hommes DT1 infertiles ont un diabete ancien frequemment complique d’une ejaculation retrograde necessitant une prise en charge adaptee et un renforcement de la collaboration entre medecine de la reproduction et diabetologues. La PMA pourrait etre plus efficace si elle etait plus precoce, cela impliquant d’evoquer systematiquement un trouble de l’ejaculation chez l’adulte jeune DT1.

La modification de genes par recombinaison homologue est un outil tres puissant d'etude de leur fonction. De nouveaux vecteurs, fondes sur le systeme de recombinase Cre-loxP du bacteriophage P1 ou, plus recemment, le systeme equivalent de levure FLP/FRT, laissent entrevoir une etude plus fine des genes mutes. Ils permettent de creer des mutations «propres», ou les genes de selection sont elimines du locus etudie et ne peuvent donc avoir d'influence sur les genes voisins. Ils permettent aussi une expression du gene mute controlee dans le temps, ce qui rend possible l'etude, a l'âge adulte, de genes dont l'absence ou la mutation sont letales au stade embryonnaire