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1.
Gynecol Obstet Fertil Senol ; 51(4): 200-205, 2023 04.
Artículo en Francés | MEDLINE | ID: mdl-36681149

RESUMEN

OBJECTIVE: New possibilities for using gametes within a couple were created by the French law of August 2, 2021 related to bioethics by opening Assisted Reproductive Technics (ART) to all women. It concerns previously self-preserved gametes, thus avoiding the need for gamete donation. The objective of our study is to evaluate the perception of these new uses by ART practitioners. METHOD: A questionnaire of twelve short questions was sent to professionals concerned with gamete donation. RESULTS: One hundred and ten professionals answered the questionnaire. The majority of them approve of the Reception of Oocytes from the Partner (ROPA), notably if there is a medical indication. Requests are rarer for the care of trans* people, and raise more questions. Although less favorable to the use of eggs from trans* men, more of them support the practice when it is an alternative to oocyte donation. CONCLUSION: The acronym EUGIC (Extension of the Use of Gametes in Intra-Conjugal) makes it possible to group together these new situations generated by the change in the French law.


Asunto(s)
Células Germinativas , Técnicas Reproductivas Asistidas , Humanos , Femenino , Oocitos , Donación de Oocito
2.
Hum Reprod Open ; 2022(4): hoac042, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36382009

RESUMEN

STUDY QUESTION: In a non-commercial national gamete donation programme, do the motivations and personality characteristics of candidate sperm and oocyte donors differ according to their parenthood status? SUMMARY ANSWER: Moderate differences exist between non-parent and parent candidate donors in motivations for gamete donation and representations as well as in personality characteristics. WHAT IS KNOWN ALREADY: Several studies have analysed the motivations and experiences of oocyte or sperm donors, but mainly in countries where gamete donation is a commercial transaction, and very few studies have reported results of personality traits using personality inventory tests. No study has specifically investigated the motivations and personality characteristics of candidate gamete donors according to parenthood status. STUDY DESIGN SIZE DURATION: A prospective study was carried out including 1021 candidate donors from 21 centres (in university hospitals) of the national sperm and egg banking network in France between November 2016 and December 2018. PARTICIPANTS/MATERIALS SETTING METHODS: In total, 1021 candidate gamete donors were included in the study. During their first visit, male (n = 488) and female candidate donors (n = 533) completed a questionnaire on sociodemographic characteristics, their motivations for donation and their representations of donation, infertility and family. Secondly, a NEO Personality Inventory (NEO-PI-R) exploring the Big Five personality traits was completed online. Results were compared between parent and non-parent candidate donors. MAIN RESULTS AND THE ROLE OF CHANCE: Altruistic values were the principal motive for donation irrespective of parenthood status. Reassurance about their fertility or preservation of sperm for future use was more often reported in non-parent than in parent candidate donors. With regard to representation of gamete donation or of the family, independently of their parenthood status, candidate donors more frequently selected social rather than biological representations. Mean personality characteristics were in the normal range. Non-parent candidate donors had higher scores on openness and depression than parents, while parent candidate donors appeared more social than non-parents. LIMITATIONS REASONS FOR CAUTION: The personality characteristics inventory was not completed by all candidate donors included in the study. However, family status did not differ between the two groups (NEO-PI-R completed (n = 525) or not), while the group who completed the NEO-PI-R had a higher educational level. This national study was performed in a country where gamete donation is subject to strict legislation. WIDER IMPLICATIONS OF THE FINDINGS: In a global context where reproductive medicine is commercialized and gamete donor resources are limited, this study found that altruism and social representations of gamete donation and family are the main motivations for gamete donation in a country which prohibits financial incentive. These findings are relevant for health policy and for gamete donation information campaigns. STUDY FUNDING/COMPETING INTERESTS: Grant from the Agence de la Biomédecine, France. The authors have nothing to disclose related to this study. TRIAL REGISTRATION NUMBER: N/A.

3.
Gynecol Obstet Fertil Senol ; 50(10): 682-688, 2022 10.
Artículo en Francés | MEDLINE | ID: mdl-35750197

RESUMEN

Many health care professionals are dealing with the issue of transgender people in their medical practice. In the field of reproduction, Trans people can benefit from fertility preservation before the introduction of hormonal treatment or surgery altering their fertility. This article, which is the result of a collaborative work of several reproductive professionals involved in the health of Trans people, provides an overview of the possibilities of fertility preservation and medically assisted reproduction techniques in France for Trans people.


Asunto(s)
Preservación de la Fertilidad , Personas Transgénero , Fertilidad , Preservación de la Fertilidad/métodos , Humanos , Reproducción , Técnicas Reproductivas Asistidas
7.
Eur J Obstet Gynecol Reprod Biol ; 253: 65-70, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32784054

RESUMEN

OBJECTIVE: To present a case series of women with borderline ovarian tumours (BOTs) who underwent oocyte vitrification in addition to fertility-sparing surgery. STUDY DESIGN: Observational study of all women referred to a French fertility preservation unit between 2015 and 2019 for counselling regarding a fertility preservation (FP) strategy after BOT fertility-sparing surgery. All eligible women underwent one or more cycles of controlled ovarian stimulation (COS) using an antagonist protocol, followed by oocyte retrieval. Metaphase II (MII) oocytes were vitrified. RESULTS: Twenty-five women with BOTs were referred during the study period. Among them, 11 women underwent at least one cycle of COS. One hundred and seven MII oocytes were vitrified. The mean number of vitrified MII oocytes per woman was 9.7 (standard deviation 5.2). Five live births were reported during follow-up of four women with vitrified oocytes: three spontaneous pregnancies, one in-vitro fertilization cycle with fresh embryo transfer, and one live birth after return of vitrified oocytes. CONCLUSION: Conservative surgery for BOTs offers a high spontaneous pregnancy rate but has a higher risk of relapse than radical treatment. Furthermore, women who undergo conservative BOT surgery have a higher risk of surgery-induced premature ovarian failure. Oocyte cryopreservation after COS appears to be an effective technique after the conservative management of BOTs in women of reproductive age. Although the available short-term data are reassuring, further long-term studies evaluating the safety and cost-effectiveness of this systematic FP strategy after BOT fertility-sparing surgery are required.


Asunto(s)
Preservación de la Fertilidad , Neoplasias Ováricas , Criopreservación , Femenino , Humanos , Recuperación del Oocito , Oocitos , Embarazo , Vitrificación
8.
Gynecol Obstet Fertil Senol ; 46(4): 395-402, 2018 Apr.
Artículo en Francés | MEDLINE | ID: mdl-29602693

RESUMEN

OBJECTIVES: The aim of this article is to question the feeling of IVF patients towards embryonic cryopreservation, in order to understand their potential reluctance to freeze embryos and their difficulties to consider the fate of their frozen embryos once their parental project completed. METHODS: Twenty-seven semi-directive interviews with homologous IVF patients were conducted. These persons were followed in two fertility centres in Marseille. RESULTS: If all the patients interviewed have accepted embryonic cryopreservation or have accepted on principle, a majority have an ambivalent attitude towards this technique. If some share the "pragmatic" vision of professionals (embryologists, technicians and gynaecologists), they are numerous to worry about a possible deterioration of embryonic quality, or again about a disrupted order of generation. Finally, it appears that patients do not anticipate the possible fate of their frozen embryos if they are uninscribed from their parental project. CONCLUSIONS: Patients are mainly ambivalent towards embryonic cryopreservation. They prioritize different rationality depending on the situations and issues they are dealing with.


Asunto(s)
Criopreservación , Embrión de Mamíferos , Fertilización In Vitro/psicología , Adulto , Toma de Decisiones , Transferencia de Embrión , Femenino , Francia , Humanos , Masculino , Persona de Mediana Edad
9.
Andrology ; 5(4): 640-663, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28622464

RESUMEN

Beside cytotoxic drugs, other drugs can impact men's fertility through various mechanisms. Via the modification of the hypothalamic-pituitary-gonadal axis hormones or by non-hormonal mechanisms, drugs may directly and indirectly induce sexual dysfunction and spermatogenesis impairment and alteration of epididymal maturation. This systematic literature review summarizes existing data about the negative impact and associations of pharmacological treatments on male fertility (excluding cytotoxic drugs), with a view to making these data more readily available for medical staff. In most cases, these effects on spermatogenesis/sperm maturation/sexual function are reversible after the discontinuation of the drug. When a reprotoxic treatment cannot be stopped and/or when the impact on semen parameters/sperm DNA is potentially irreversible (Sulfasalazine Azathioprine, Mycophenolate mofetil and Methotrexate), the cryopreservation of spermatozoa before treatment must be proposed. Deleterious impacts on fertility of drugs with very good or good level of evidence (Testosterone, Sulfasalazine, Anabolic steroids, Cyproterone acetate, Opioids, Tramadol, GhRH analogues and Sartan) are developed.


Asunto(s)
Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/etiología , Fertilidad/efectos de los fármacos , Infertilidad Masculina/inducido químicamente , Espermatozoides/efectos de los fármacos , Animales , Criopreservación , Daño del ADN , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/patología , Efectos Colaterales y Reacciones Adversas Relacionados con Medicamentos/fisiopatología , Preservación de la Fertilidad/métodos , Humanos , Infertilidad Masculina/patología , Infertilidad Masculina/fisiopatología , Infertilidad Masculina/terapia , Masculino , Medición de Riesgo , Factores de Riesgo , Conducta Sexual/efectos de los fármacos , Bancos de Esperma , Espermatogénesis/efectos de los fármacos , Espermatozoides/patología
10.
Environ Sci Pollut Res Int ; 24(8): 6844-6852, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27126867

RESUMEN

Passive samplers are theoretically capable of integrating variations of concentrations of micropollutants in freshwater and providing accurate average values. However, this property is rarely verified and quantified experimentally. In this study, we investigated, in controlled conditions, how the polydimethylsiloxane-coated stir bars (passive Twisters) can integrate fluctuating concentrations of 20 moderately hydrophilic to hydrophobic pesticides (2.18 < Log K ow < 5.51). In the first two experiments, we studied the pesticide accumulation in the passive Twisters during high concentration peaks of various durations in tap water. We then followed their elimination from the passive Twisters placed in non-contaminated water (experiment no. 1) or in water spiked at low concentrations (experiment no. 2) for 1 week. In the third experiment, we assessed the accuracy of the time-weighted average concentrations (TWAC) obtained from the passive Twisters exposed for 4 days to several concentration variation scenarios. We observed little to no elimination of hydrophobic pesticides from the passive Twisters placed in non-contaminated water and additional accumulation when placed in water spiked at low concentrations. Moreover, passive Twisters allowed determining accurate TWAC (accuracy, determined by TWAC-average measured concentrations ratios, ranged from 82 to 127 %) for the pesticides with Log K ow higher than 4.2. In contrast, fast and large elimination was observed for the pesticides with Log K ow lower than 4.2 and poorer TWAC accuracy (ranging from 32 to 123 %) was obtained.


Asunto(s)
Dimetilpolisiloxanos/análisis , Monitoreo del Ambiente , Agua Dulce/química , Modelos Teóricos , Plaguicidas/análisis , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente/instrumentación , Monitoreo del Ambiente/métodos , Interacciones Hidrofóbicas e Hidrofílicas , Plaguicidas/química , Manejo de Especímenes , Contaminantes Químicos del Agua/química
11.
Clin Genet ; 91(2): 217-232, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27779748

RESUMEN

Infertility, defined by the inability of conceiving a child after 1 year is estimated to concern approximately 50 million couples worldwide. As the male gamete is readily accessible and can be studied by a simple spermogram it is easier to subcategorize male than female infertility. Subjects with a specific sperm phenotype are more likely to have a common origin thus facilitating the search for causal factors. Male infertility is believed to be often multifactorial and caused by both genetic and extrinsic factors, but severe cases of male infertility are likely to have a predominant genetic etiology. Patients presenting with a monomorphic teratozoospermia such as globozoospermia or macrospermia with more than 85% of the spermatozoa presenting this specific abnormality have been analyzed permitting to identify several key genes for spermatogenesis such as AURKC and DPY19L2. The study of patients with other specific sperm anomalies such as severe alteration of sperm motility, in particular multiple morphological anomalies of the sperm flagella (MMAF) or sperm unability to fertilize the oocyte (oocyte activation failure syndrome) has also enable the identification of new infertility genes. Here we review the recent works describing the identification and characterization of gene defects having a direct qualitative effect on sperm morphology or function.


Asunto(s)
Aurora Quinasa C/genética , Infertilidad Masculina/genética , Proteínas de la Membrana/genética , Espermatozoides/patología , Femenino , Humanos , Infertilidad Masculina/patología , Masculino , Oocitos/crecimiento & desarrollo , Motilidad Espermática/genética , Cola del Espermatozoide/metabolismo , Cola del Espermatozoide/patología , Espermatogénesis/genética , Espermatozoides/crecimiento & desarrollo , Teratozoospermia/genética , Teratozoospermia/patología
12.
Clin Genet ; 91(2): 208-216, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27779755

RESUMEN

Azoospermia, defined by the absence of sperm in the ejaculate, is estimated to affect up to 1% of men in the general population. Assisted reproductive technologies have revolutionized the treatment of infertility, and some azoospermic men, those with a post-meiotic defect, can conceive following the use of viable spermatoza recovered from testicular or epididymal biopsies. Although male infertility is a multifactorial disease, it is believed that genetic factors are predominant in the etiology of azoospermia and severe oligozoospermia. Despite that assumption, substantiated by the high number of infertile knockout (KO) mice and the even higher number of genes expressed essentially in the testis, little is known about the pathophysiology of reduced sperm production, its primary causes or the genetic and epigenetic consequences for the gamete and the future conceptus. The identification of genetic abnormalities is therefore paramount to understand spermatogenesis, to adopt the best course of action for the patient and to provide adequate genetic counseling. We provide here a review of the recent literature on the genetics of azoospermia and oligozoospermia, focusing on defects directly altering sperm production. New sequencing technologies are contributing to the rapid evolution of the recent field of infertility genetics.


Asunto(s)
Azoospermia/genética , Infertilidad Masculina/genética , Oligospermia/genética , Espermatozoides/patología , Animales , Azoospermia/patología , Regulación del Desarrollo de la Expresión Génica , Asesoramiento Genético , Humanos , Infertilidad Masculina/patología , Masculino , Ratones , Ratones Noqueados , Oligospermia/patología , Técnicas Reproductivas Asistidas , Espermatozoides/crecimiento & desarrollo
13.
Environ Sci Pollut Res Int ; 23(1): 14-22, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26115706

RESUMEN

Subsurface lateral flow in both texture-contrast soils and catchments with shallow bedrock is suspected to be a non-point source of contamination of watercourses by pesticides used in agriculture. As a case study, the north of the Beaujolais region (eastern France) provides a favorable environment for such contamination due to its agro-pedo-climatic conditions. Environments seen in the Beaujolais region include intense viticulture, permeable and shallow soils, steep hillslopes, and storms that occur during the periods of pesticide application. Watercourse contamination by pesticides has been widely observed in this region, and offsite pesticide transport by subsurface lateral flow is suspected to be involved in diffuse and chronic presence of pesticides in surface water. In order to confirm and quantify the potential role of such processes in pesticide transfer, an automated trench system has been designed. The trench was set up on a steep farmed hillslope in a texture-contrast soil. It was equipped with a tipping bucket flow meter and an automatic sampler to monitor pesticide concentrations in lateral flow at fine resolution, by means of a flow-dependent sampling strategy. Four pesticides currently used in vine growing were studied to provide a range of mobility properties: one insecticide (chlorpyrifos-methyl) and three fungicides (spiroxamine, tebuconazole, and dimethomorph). With this system, it was possible to study pesticide concentration dynamics in the subsurface lateral flow, generated by substantial rainfall events following pesticide applications. The experimental design ascertained to be a suitable method in which to monitor subsurface lateral flow and related transfer of pesticides.


Asunto(s)
Plaguicidas/análisis , Contaminantes del Suelo/análisis , Contaminantes Químicos del Agua/análisis , Agricultura , Cloropirifos/análogos & derivados , Francia , Fungicidas Industriales , Suelo , Vitis , Movimientos del Agua
14.
Anal Bioanal Chem ; 406(11): 2559-70, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24493337

RESUMEN

Although experimental design is a powerful tool, it is rarely used for the development of analytical methods for the determination of organic contaminants in the environment. When investigated factors are interdependent, this methodology allows studying efficiently not only their effects on the response but also the effects of their interactions. A complete and didactic chemometric study is described herein for the optimization of an analytical method involving stir bar sorptive extraction followed by thermal desorption coupled with gas chromatography and tandem mass spectrometry for the rapid quantification of several pesticides in freshwaters. We studied, under controlled conditions, the effects of thermal desorption parameters and the effects of their interactions on the desorption efficiency. The desorption time, temperature, flow, and the injector temperature were optimized through a screening design and a Box-Behnken design. The two sequential designs allowed establishing an optimum set of conditions for maximum response. Then, we present the comprehensive validation and the determination of measurement uncertainty of the optimized method. Limits of quantification determined in different natural waters were in the range of 2.5 to 50 ng L(-1), and recoveries were between 90 and 104 %, depending on the pesticide. The whole method uncertainty, assessed at three concentration levels under intra-laboratory reproducibility conditions, was below 25 % for all tested pesticides. Hence, we optimized and validated a robust analytical method to quantify the target pesticides at low concentration levels in freshwater samples, with a simple, fast, and solventless desorption step.


Asunto(s)
Agua Dulce/química , Cromatografía de Gases y Espectrometría de Masas/métodos , Plaguicidas/aislamiento & purificación , Extracción en Fase Sólida/métodos , Contaminantes Químicos del Agua/aislamiento & purificación , Plaguicidas/química , Extracción en Fase Sólida/instrumentación , Espectrometría de Masas en Tándem/métodos , Contaminantes Químicos del Agua/química
15.
Reprod Biomed Online ; 24(3): 321-30, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22285245

RESUMEN

Sperm banking is an important procedure to preserve fertility before cancer therapy. The aim of this study was to comprehensively analyse cryopreservation activity retrospectively for 1080 patients referred to the sperm bank for sperm cryopreservation before cancer treatment. This study included 1007 patients diagnosed with testicular cancer (TC) (41.7%), lymphoma (26%), other haematological cancers (9.4%) or other types of cancer (22.8%); of these, 29 patients did not produce any semen sample and cryopreservation was impossible for 67 patients. Semen characteristics before treatment were within normal ranges, except moderate asthenospermia. Sperm concentration was significantly lower in TC than in non-TC. Straws from 57 patients (6.3%) were used in assisted reproductive technologies, which led to a 46.8% cumulative birth rate. Straws were destroyed for 170 patients (18.7%) and 140 patients performed semen analyses after cancer therapy. After an average delay of 22.5 months after the end of therapy, 43 patients (30.7%) exhibited azoospermia. This study of a large population of cancer patients revealed a high level of successful sperm storage. Utilization of cryopreserved spermatozoa led to good chances of fatherhood. Nevertheless, sperm banks should be aware of the low rates of straw use and straw destruction by cancer patients.


Asunto(s)
Criopreservación/métodos , Preservación de la Fertilidad/estadística & datos numéricos , Neoplasias/terapia , Espermatozoides , Adolescente , Adulto , Enfermedad de Hodgkin/complicaciones , Enfermedad de Hodgkin/terapia , Humanos , Infertilidad Masculina/etiología , Masculino , Neoplasias/complicaciones , Estudios Retrospectivos , Análisis de Semen , Neoplasias Testiculares/complicaciones , Neoplasias Testiculares/terapia
16.
Gynecol Obstet Fertil ; 39(9): 497-500, 2011 Sep.
Artículo en Francés | MEDLINE | ID: mdl-21820346

RESUMEN

With the improvement of the anticancerous treatments, the preservation of the feminine fertility before gonadotoxic treatment tends at present to stand out as a legal obligation, with a duty of information to patients. When emergency IVF can be performed, the cryopreservation of embryos is the best mastered method which offers most chances to patients to obtain a pregnancy after cancer remission thanks to the transfer of frozen embryos. This article proposes an overview about the indications, the feasibility and the ethical and practical limitations of IVF emergency for embryo freezing before gonadotoxic anticancerous treatment.


Asunto(s)
Criopreservación , Embrión de Mamíferos , Preservación de la Fertilidad/métodos , Fertilización In Vitro , Antineoplásicos/efectos adversos , Transferencia de Embrión , Estudios de Factibilidad , Femenino , Preservación de la Fertilidad/ética , Fertilización In Vitro/ética , Humanos , Infertilidad Femenina/etiología , Embarazo , Radioterapia/efectos adversos
17.
J Gynecol Obstet Biol Reprod (Paris) ; 40(6): 503-7, 2011 Oct.
Artículo en Francés | MEDLINE | ID: mdl-21665383

RESUMEN

OBJECTIVES: An amendment to the French bioethics law allowing children conceived by gamete donation to know the identity of donors is proposed, while no study can assess the proportion of parents in France that disclose the nature of conception to their donor conceived offspring. The aim of our study was to know whether couples who wish to inform their offspring actually did it. PATIENTS AND METHODS: We sent a questionnaire to parents who had expressed an intention to disclose the nature of conception to their future offspring conceived by sperm donation. This allowed us to evaluate the number of couples who inform their offspring, and the couple and offspring feelings when information was given. RESULTS: Among 38 questionnaires sent, 20 couples answered. Fourteen informed their offspring about the nature of conception, most having lived serenely this moment. 47% of offspring have reacted with indifference. While 19 couples informed their friends or family, six couples did not inform their offspring, and two of them no longer want to disclose anymore. CONCLUSION: Careful thought before the beginning of assisted reproductive technology and support after birth are needed to help couples communicate information to their offspring. Without this communication, any policy of openness to know donor related data seems vain.


Asunto(s)
Composición Familiar , Relaciones Padres-Hijo , Espermatozoides , Obtención de Tejidos y Órganos , Revelación de la Verdad , Niño , Hijo de Padres Discapacitados/psicología , Hijo de Padres Discapacitados/estadística & datos numéricos , Recolección de Datos , Femenino , Humanos , Infertilidad Masculina , Masculino , Embarazo , Medio Social , Encuestas y Cuestionarios , Obtención de Tejidos y Órganos/ética , Revelación de la Verdad/ética
18.
Gynecol Obstet Fertil ; 38(9): 532-5, 2010 Sep.
Artículo en Francés | MEDLINE | ID: mdl-20705499

RESUMEN

Men with spinal cord injury present a unique infertile population. Only 10 % of them can father children without medical assistance, owing to potential impairments in erection, ejaculation and semen quality. The algorithm typically followed is to retrieve semen by Penile Vibratory Stimulation, in case of failure by Electro Ejaculation. Most of these patients have normal sperm concentrations but abnormally low sperm motility and vitality in the ejaculate. The reasons for poor semen quality in spinal cord injured men are reviewed. If semen cannot be obtained by Electro Ejaculation, or if the ejaculate from Penile Vibratory Stimulation or Electro Ejaculation contains an insufficient quantity or quality of sperm for in vitro fertilization with intracytoplasmic sperm injection, then retrieval of sperm from reproductive tissues is attempted. Despite abnormal semen quality, successful pregnancies with sperm from spinal cord injured male partners have occurred by intravaginal insemination, intrauterine insemination, and in vitro fertilization with intracytoplasmic sperm injection. The prevailing pregnancy and fecundity rates in couples with a spinal cord injured male partner are reviewed.


Asunto(s)
Infertilidad Masculina/etiología , Índice de Embarazo , Técnicas Reproductivas Asistidas , Traumatismos de la Médula Espinal/complicaciones , Eyaculación , Femenino , Humanos , Infertilidad Masculina/fisiopatología , Infertilidad Masculina/terapia , Inseminación Artificial Homóloga , Masculino , Embarazo , Análisis de Semen , Recuperación de la Esperma
20.
Gynecol Obstet Fertil ; 37(11-12): 895-900, 2009.
Artículo en Francés | MEDLINE | ID: mdl-19819743

RESUMEN

Sex chromosome behaviour fundamentally differs between male and female meiosis. In oocyte, X chromosomes synapse giving a XX bivalent which is not recognizable in their morphology and behaviour from autosomal bivalents. In human male, X and Y chromosomes differ from one another in their morphology and their genetic content, leading to a limited pairing and preventing genetic recombination, excepted in homologous region PAR1. During pachytene stage of the first meiotic prophase, X and Y chromosomes undergo a progressive condensation and form a transcriptionally silenced peripheral XY body. The condensation of the XY bivalent during pachytene stage led us to describe four pachytene substages and to localize the pachytene checkpoint between substages 2 and 3. We also defined the pachytene index (PI=P1+P2/P1+P2+P3+P4) which is always less than 0.50 in normal meiosis. XY body undergoes decondensation at diplotene stage, but transcriptional inactivation of the two sex chromosomes or Meiotic Sex Chromosome Inactivation (MSCI) persists through to the end of spermatogenesis. Sex chromosome inactivation involves several proteins, some of them were now identified. Two isoforms of the HP1 protein, HP1beta and HP1gamma, are involved in the facultative heterochromatinization of the XY body, but the initiation of this process involves the phosphorylation of the protein H2AX by the kinase ATR whose recruitment depends on BRCA1. Extensive researches on the inactivation of the sex chromosomes during male meiosis will allow to a better understanding of some male infertilities.


Asunto(s)
Meiosis/fisiología , Cromosomas Sexuales/fisiología , Homólogo de la Proteína Chromobox 5 , Cromosomas Humanos X/fisiología , Cromosomas Humanos Y/fisiología , Femenino , Humanos , Masculino , Ovario/fisiología , Recombinación Genética , Espermatocitos/fisiología
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