CYTOGENETIC

Author: CUSCO MARTI IVON.
Year: 2002.
University: BARCELONA [www.ub.es].
Place of defense: FACULTAD DE MEDICINA.
Place of preparation: FACULTAD DE MEDICINA.

Summary: The atrófia muscle spinal (AME) is a neuromuscular disease with a pattern of inheritance antosómica recessive. It has an incidence of 1/6000-1/10000 t and a frequency of carriers 1/34-1/50. This disease is classified into 4 phenotypes depending on the age of onset and progression of symptoms. It is believed that the gene causing dela AME is the SMN1 because their loss or alteration is detected in almost all patients. There is a homolog gene called SMN2 that is not responsible for the disease, but it seems that acts on the expression of the phenotype end. This thesis has been studying the presence and frequency of gene hybrids SMN1-SMN2, and have characterized different point mutations, one of them (C.399-402 of AGAG) specific to the Spanish people of common origin and that represents the mutation most frequently described. We have also developed two methods of qualitative analysis of genes SMN1 and SMN2 to determine carriers of the disease, and characterize the effect of gene SMN2 on phenotype end.

Author: RIGOLA TOR M. ANGELS.
Year: 2003.
University: AUTÓNOMA DE BARCELONA [www.uab.es].
Place of defense: FACULTAD DE MEDICINA.
Place of preparation: ESCUELA DE DOCTORADO Y DE FORMACIÓN CONTINUADA.

Summary: The precise characterization of the chromosomal regions involved in chromosomal abnormalities is of the utmost importance both for the diagnosis and prognosis of many diseases, and for providing valuable information for the identification of genes involved in them. The overall objective of this study was to detect and identify chromosomal alterations unbalanced, both constitutional and acquired by the technique of Comparative Genomic Hybridization (CGH). This technique, originally described to study alterations acquired neopalias human allows analyze DNA from the imbalances problem of the entire genome with no need for cell culture or obtaining chromosomes metafásicos. This has facilitated the characterization of many chromosomal abnormalities that went unnoticed, or that they could not come to be identified through conventional cytogenetic techniques (mainly bands G). Once perfected the art of CGH, in our laboratory, has been applied to test their usefulness in diagnosing prenatal and postnatal structural chromosomal abnormalities detected, but not identified previously through G bands in amniocitos and in lymphocytes. In the six cases reviewed has achieved a precise identification of chromosomal alterations showing its usefulness in characterizing trisomías and monosomías partial constitutional. It has also allowed genotipo - fenotipo build partnerships and identify regions comosómicas where they located the genes responsible for the relevant clinical changes. One example is the detection of delección in the region 18pter. That has enabled associate for the first time with mental retardation due to the loss of the gene coding for TGIF (transforming growing-interacting factor) located in 18p11.3. Another contribution of the CGH has been the identification of a small gain of chromosome and, as might be expected in two male patients with karyotype 46, XX. However, the unexpected discovery of two regions PARX1 (instead of one) in one of the patients has highlighted the need to reassess the XX males using this methodology in order to determine whether the phenotypic differences observed in these patients might be associated with the presence of one or two regions PARX1. Most of the study has focused on the characterization of chromosomal imbalances acquired in transitional cell tumors (CBT) urotelilaes: bladder (24 patients) and renal pelvis (10 patients) and in renal tumors (8 patients). The goal we considered was to provide information on the genomic imbalances in tumors uroteliales little studied and evaluate the effectiveness d in the CGH detect imbalances in clones minority. The results showed that the CGH can identify global imbalances genome tumor in many cases could not be detected and characterized with conventional cytogenetic techniques. However, the CGH is not valid for characterized with conventional cytogenetic techniques. However, the CGH is not valid for characterizing variability and intratumoral imbalances that can play a pivotal role in the development and progression of the tumor. CGH studies of renal tumors confirmed the results obtained through G bands such as papillary tumors that there are many numerical changes, the most frequent change in the tumor cell clear is the loss of 3p in oncocytomas imbalance more frecuent 8 and is the 81d loss of chromosome 1. Profiles of CGH CBT uroteliales have allowed evidence that tumors invasive and non-invasive high-grade bladder can form a group of their own (within the bladder cancer) characterized by their high degree of volatility. In CBT invasive bladder, it has been observed that tumors with solid pattern presented gains 2p and 13q as the most frequent alterations while tumors with standard mixed sólido-papilar imbalances have been more frequent gain of 1q, 11q13 and 17q and losses 11p, 11q and 13q. The pattern of chromosomal imbalances detected by CGH invasive bladder tumors in high-grade is very similar suggesting the existence of a life of tumor progression converged in the last stages in the development of bladder cancer. The CGH has allowed characterize as a frequent chromosomal alterations in renal pelvis CBT loss 9q. Moreover, most of imbalances in such tumors, so little studied for the moment, have been previously described in bladder cancer confirming that these tumors have a common biological behavior and genetic abnormalities similar. In summary, our results confirm that the CGH provides very valuable information that can not be obtained if you just use the analysis bands G. However, since these cytogenetic techniques to observe both the balanced rearrangements (impossible to be detected by CGH) and the variability karyotype intratumoral, or mosaicismos constitutional a lesser degree, are now extremely useful in such studies.

Author: GONZÁLEZ SÁNCHEZ MÓNICA.
Year: 2003.
University: COMPLUTENSE DE MADRID [www.ucm.es].
Place of defense: FACULTAD DE CC BIOLÓGICAS.
Place of preparation: FACULTAD DE CC BIOLÓGICAS.

Summary: It has continued the process of selection for high and low (Hm) (Lm) transmission rate of Bs through parental initiated by Rosato et al. In 1996 in the native breed corn Pisingallo. In this selection process the authors concluded that the rate of transmission of male Bs (Ttm) is controlled genetically and that the gene or genes responsible are found on chromosomes A. The study of the offspring of crosses OBx2B and 2Bx2B made in Buenos Aires and Madrid for two generations, has permitico find that the differences are between the lines and Lm Hm are due to the phenomenon of preferential fertilization, and the presence or Bs in the female parent, or the environment have an influence on the Ttm. We extracted hybrid F1m between the lines, which were uniforms and filed a Ttm between the lines. To estimate the number of genes implicdos in controlling the Ttm, was obtained F2m by autofecundació a hybrid HmLm with 2 Bs. Using the formula of Wright concluded that the Ttm is controlled by a locus, we call mBt (male B-transmissión) with two alleles, mBth and mBtl. The fen mBt serving at heploide in ovocélula during the process of fertilization, determining which of the two nuclei espemáticos fecundará to avocélula. It also has continued the selection process initiated by Rosato et al (1996) to high (Hf) and low (Lf) transmission rate of Bs through maternal in the same race native corn, determining that the gene (or genes) that ocntrola the Ttf is located on chromosomes A. It was concluded that this gene (or genes), which called fBt (female b-transmissión), serving at diploide.el allele fBt is dominant and cause the loss of B during meiosis, which is responsible for causing the low Ttf that it was found on the line Lf and hybrids. It has studied the behavior of certain chromosomes in the cells of the table of the antenna. It has been observed that in this tissue chromosome instability, are common genotypes presenting more chromosomal instabilities are frequent. Genotypes presenting more instabilities cormosómicas also show greater fercuencia cell with TUNEL staining, indicating that the chromosome instability have resulted in an acceleration of PCD. It can be concluded that the chromosomal instabilities that are seen in the table are important in the process of PCD who suffers this tissue, and thus influence the development of microspore to form mature pollen grains. It is concluded that the rate of transmission of cormosomas B in the race corn Pisingallo is controlled by at least two different genes. It is argued that the maintenance of stable polymorphism Bs for corn is an example of the so-called conflict between coevolución genomes.

Author: HERNANDO DAVALILLO CRISTINA.
Year: 2004.
University: AUTÓNOMA DE BARCELONA [www.uab.es].
Place of defense: FACULTAD DE CIENCIAS.
Place of preparation: ESCUELA DE POSTGRADO UAB.

Summary: Congenital malformations have a very diverse etiology. In most cases, are the result of a set of genetic alterations detected by the presence of numerical or structural chromosomal abnormalities. The clinical consequences arising out, depend on the size of chromosomal segment involved, the number and function of genes present in the fragment. The emergence of new technologies has enabled the identification of molecular cytogenetic abnormalities than with conventional techniques bands (band G) went unnoticed or could not be characterized, in the case of small genetic alterations unbalanced (microdeleciones and microduplicaciones) as balanced ( translocations complex and / or cryptic). This thesis has been based on the characterization of various chromosomal abnormalities in prenatal diagnosis and postnatal, by applying techniques conventional cytogenetic and molecular cytogenetics: in situ hybridization fluoresecente (FISH) and comparative genomic hybridization (CGH). This has been achieved in deepening the role that develop these alterations in the etiology of certain birth defects and other abnormal phenotypes helping to provide a Council Genetic much more precious.

Author: POYATOS ANDUJAR DAVID.
Year: 2004.
University: AUTÓNOMA DE BARCELONA [www.uab.es].
Place of defense: FACULTAD DE CIENCIAS.
Place of preparation: ESCUELA DE POSTGRADO.

Summary: The syndromes Prader (PWS) and Angelman (HS) are two of developmental and behavioral syndromes that occur with a frequency 1/15.000-20.000 newborns. They result from the loss of physical or functional genes regulated by the imprint within the region 15q11-q13. PWS is associated with the loss of expression of paternal alleles, while the SA is associated with the loss of expression of maternal allele. Approximately 70% of patients present SPW deletion in chromosome paternal, 20-30% disomía uniparental maternal and 1% failing mark. In patients SA presented the 70% deletion in chromosome mother, the 6% disomía uniparental father, the 2-7% failing mark, the 4-10% mutation of the gene UBE3A and in the 10-12% etiology is unknown . The molecular cytogenetic diagnosis of these syndromes are usually done using combianción several techniques because the genetic base is complex. Our laboratory in 1991 began studies on cytogenetics, in 1993 studies FISH, in 1994 the analysis of micro-and in 1996 the analysis of methylation. From our experience we propose a molecular diagnosis algorithm. We have analyzed between the years 1991-2000, 151 patients and six liquids amnióticos with suspected PWS and 147 patients and two liquid amnióticos with suspected SA from the Spanish territory. The techniques used have been studying the karyotype through G bands, fluorescent in situ hybridization, the microsatellite analysis and the analysis of methylation with chemiluminescent detection. The diagnosis of Prader-Willi syndrome has been confirmed in 40 patients, 28 caused by delección five disomía uniparental, two default mark and in five has not been determined aetiology. The SA has been confirmed in 47 patients, 39 per delección, four disomía uniparental and four has not been determined aetiology. Fifteen patients with suspected SA and study molecular normal clinic have presented a typical SA, which have been considered candidates to submit a mutation in the gene UBE3A or patients of unknown etiology. The característics clinics, patients have been collected by medical specialists, correlacionándola to aetiology. Patients with Prader-Willi syndrome deletion have not presented significant differences with respect to other groups in neonatal hypotonia, obsedidad, hipergrafía, developmental delay, hypogonadism, small hands and feet, dental anomalies, saliva viscose, changes in behavior and sleep problems. Only differences were observed in feeding problems (93% vs. 50%, p = 0070) between deletion and disomía uniparental and facies characteristics (100% vs. 50%, p = 0069) among patients with deletion and failing mark. Patients SA deletion have not reported significant differences compared to the other etiologies in developmental delay and language, ataxia, frequent laughter, hands flutter, hipermotricida, inattention, microcephaly, seizures, abnormal EEG, occipital flat, wide mouth , babeo hypopigmentation. The periods have been similar to those of previous studies. In contrast, there have been differences between deletion and disomía uniparental in feeding problems (100% vs. 0%, p = 0008), protusión of the tongue (73% vs. 0%, p = 0011), prognatia (57% vs. 0 %, p = 0051) and communication gestures (23% vs. 75%, p = 0060). These results indicate that the dismorfismo facial and communication gestures are less severe in patients with disomía. However, we are unable to 8 conclui 3d7 r that the phenotype of these patients may be less severe than that of patients with deletion. This work has allowed a greater understanding of the molecular and clinical these two syndromes that has led us to be a referral center and advisers to families affected.

Author: ORTIZ ZARRAGOITIA MAREN.
Year: 2004.
University: PAÍS VASCO [www.ehu.es].
Place of defense: FACULTAD DE CIENCIA Y TECNOLOGÍA.
Place of preparation: UPV/EHU.

Author: PUJOL MASANA AҏDA.
Year: 2004.
University: AUTÓNOMA DE BARCELONA [www.uab.es].
Place of defense: FACULTAD DE MEDICINA.
Place of preparation: ESCUELA DE POSTGRADO.

Summary: Cytogenetic analysis of the first polar corpúsculo (1CP) allows an indirect characterization of oocytes at metaphase II (MII) without compromising its ability to reproduce. This allows, within a program of in vitro fertilization (IVF), develop a variant of genetic diagnosis preimplantacional in which he examines the 1CP (DGP-1CP). The overall objective of this work is to study the incidence of aneuploidía in the female germ line and the first stages of embryonic development. Oocytes were used discarded from IVF cycles to develop a methodology for fluorescent in situ hybridization (FISH) can detect nine chromosomes in 1CPs and MII. So far, the absence of chromosome s cromátides in 1CP were considered artifacts, but the valuation of complementarity 1CP-MII done notes that they are only a minority (25.8%). Both frequency aneuploidía obtained for the nine chromosomes studied (47.5%) as the estimated risk of aneuploidía for 23 chromosomes (57.2%) are very high. The estimated risk for abnormal chromosome segregation analyzed is 0.89%. Various mechanisms have been identified for generation of aneuploidies in the oocyte: separation early cromátides sisters (observed more frequently in the 1CP that the MII) and no-disyunción chromosome counterparts in meiosis and anomalous segregation in mitosis of the stage proliferative of germline (gonadal mosaicism). This phenomenon has been detected in 25.7% of patients and analyzed ago recommended prenatal diagnosis for patients who become pregnant after a DGP-1CP. Applying DGP-1CP in women with normal karyotype (elderly women), the incidence of aneuplodía for the nine chromosome has been 60.4%, confirming that this group is a group of risk for the presence of aneuploidies. Aplicándolo two patients carrying translocations Robertsonianas has found a very high rate aneuploidía for chromosomes not involved in the translocation (91.7% i 72.7%), regardless of the alterations observed in the chromosome translocation. Analysis of aneuploidies in blastómeros of patients and carriers of reciprocal translocations shows a high rate of chromosomal aneuploidies in not involved in the translocation (60.3%) and also a high percentage of mosaicism (58.7%), taking into account both chromosomes implicated as not involved in the translocation. Embryos were found normal or balanced for the translocation aneuploids but for other chromosomes. It seems necessary to study sequential segregation of chromosomes involved in the translocation and the aneuploidies other chromosomes, in patients with translocations. To validate the interpretation of results of the FISH analysis aneuplodía in proliferating cells have been studied in cells stadium G0 (Sertoli cells) and proliferating cells (lymphocytes). By applying FISH cells in proliferation is estimated that 10.8% of double marks in excess are, in comparison with those found in non-proliferating cells, are not signals parties, but due to the replication process. Application of FISH in proliferating cells, such as blastómeros, could hamper the interpretation of the results of FISH. It would be necessary to include bookmarks the beginning or the end of replication to be used simultaneously with diagnostic probes in blastómeros FISH. The DGP for detection and aneuploidies, is an over procedures that are available to provide patients with r 8 iesgo au 31st nque should assess, in each case, if your application can benefit.

Author: GUTIERREZ MATEO CRISTINA MERCEDES.
Year: 2004.
University: AUTÓNOMA DE BARCELONA [www.uab.es].
Place of defense: FACULTAD DE MEDICINA.
Place of preparation: ESCUELA DE POSTGRADO.

Summary: The Diagnostics Genetic Preimplantacional (PGD), using fluorescent in situ hybridization (FISH) to analyze and identify chromosomes nine cromosómicamente abnormal embryos, has lead to increase pregnancy rates in certain groups of patients. However, this strategy has certain limitations, the most important being the number of chromosomes that can be analyzed. In this study we evaluated the reliability of comparative genomic hybridization (CGH) to discuss how the whole chromosome complement an alternative to using PGD FISH. The CGH by providing a more complete analysis of karyotype, would transfer just cromosómicamente normal embryos, which are the most suitable to produce a viable pregnancy. The validation of the CGH has been conducted to assess the complementarity between the results obtained in the first corpúsculos polar (1CP) and those in the oocyte at metaphase II (MII). We have analyzed a total of 106 eggs donated by 71 women. In 81 cases analyzed both the MII how 1CP, while in 25 cases analyzed only one member of the couple. The efficiency of the CGH has been 80.1% and the rate of 87.4% of complementarity. In some cases it has detected a skirt of complementarity between 1CP and MII, explained by the existence of a gonadal mosaicism in some of these patients. The incidence of aneuploidies has been 45.3%. We have detected a total of 80 aneuploidies affecting almost all chromosomes, but, in general, the small chromosomes tended to show a higher incidence. Nearly 80% of these are for aneuploidies chromosomes that are not analyzed with the strategy FISH nine chromosomes, since these chromosomes are not responsible for offspring tirsómica feasible nor of the majority of savings spontaneous. However, our data show that these errors chromosomes must be frequent at the time of conception, but its implementation fails, causing even decline in the rates of implantation. Approximately 37% of couples 1CP-MIII aneuploids errors chromosomes were not included in the current screening aneuploidies and therefore would have been incorrectly diagnosed as normal range using PGD for FISH analysis nine chromosomes. We have found a greater proportion of abnormal oocytes group of older women (60.7%), compared with the group of oocytes in women under 35 years of age (28%). These differences were statistically significant. On the other hand, have also been used in this study techniques FISH i cenM-FISH to differentiate between chromosome abnormalities and chromatids, which is not always possible using the CGH. These two techniques have indicated the existence of two mechanisms aneuploidía, the precocious sister chromatid separation (PSSC) (68.1%) and no-disyunción chromosome counterparts (31.9%). This work has also demonstrated the reliability of the CGH not only to detect changes in the number of copies of any chromosome in 1CP and oocytes at metaphase II, but also to detect segregations of unbalanced translocations maternal. The CGH therefore can be used in PGD for translocations, both for the analysis of chromosomes involved as of chromosomes that are not involved in the reorganization. Finally, the CGH have been applied to study 1CPs a PGD for a woman age mater 8 na avanz 446 ada. This protocol is consistent with an embryo transfer to day +4, without freezing embryos. In conclusion, our results suggest that the ideal strategy in PGD is the analysis of the entire chromosome as some aneuploidies not included in the analysis with FISH could, in fact, common at the time of conception.

Author: CLIMENT BATALLER JOAN.
Year: 2004.
University: VALENCIA [www.uv.es].
Place of defense: BIBLIOTECA DEL CAMPUS DE BURJASSOT.
Place of preparation: FACULTAD DE BIOLOGÍA.

Summary: Despite the current consensus on the choice of systemic therapy adjyuvante based on clinical and histological criteria, 25% of patients with breast cancer without lymph node involvement (CMGo) presented relapse and eventually die because of the disease. The gene expression profiles of tumors of breast cancer represent a powerful predictor of survival, however, these systems analysis of the human genome are not yet applied in clinical practice. This thesis examines the possibility of creating a genomic predictor of the risk of relapse in patients with CMGo by analyzing the number of copies of DNA in the tumor genomes using genomic arrays. Methods: We studied by Comparative Genomic Hybridization of DNA microarrays (array-CGH) a total of 185 biopsies obtained from tumor patients diagnosed CMGo and treated at the University Teaching Hospital in Valencia. The median follow-up was 82 months (range, 11-218). After surgery, 90 patients received adjuvant chemotherapy based on antracilcinas (group JI), while the 95 remaining did not receive quimoterapia (NT group). For the study of correlations between genomic data obtained with the clinical characteristics and survival of patients using the statistical model of Cox. The level of significance of associations was corrected through tests more appropriate statistical adjustment for multiple comparisons. Results: Analysis of the genomic tumor CMGo show a characteristic genomic profile based on profit / amplification of chromosomal regions 1q31-q41, 8q21-q24, 17q12-q21 and 20q12q13 and loss genomics 8p21-p23, 11q21-q24, 16 q21-q23 and 17p13. The winnings specific clones contained in the regions 1q, 16q and loss of 16q associated with the levels of expression of estrogen receptors, whereas no expression of the progesterone receptor correlated with the loss genomics 4p and 5q . The distribution of genomic abnormalities was similar in both treatment groups (vs. BC. NT). In none of the group AC or BAC clones analyzed's correlated with the survival of the patients. However, the NT group noted that the loss of genomic a group of 29 clones contained in two chromosomal regions 8p21-p23 and 11q21-q25. Directly associated with disease-free survival and relapse patients. Those patients with loss of these genomic clones have a 62% relapse if they have not received chemotherapy treatment, whereas if they have received treatment relapse rate was 16%. Conclusions: The genomic profile of the tumor cells can predict the clinical outcome of patients in both groups of patients treated with CMGo differently. The array CGH analysis of a number of clones covering the genomic regions 8p21-23 and 11q21-24 could select candidates to receive adjuvant chemotherapy based on anthracyclines independently from the rest of clinical features.

Author: BARAGAÑO RIO LUCIA.
Year: 2004.
University: OVIEDO [www.uniovi.es].
Place of defense: FACULTAD DE MEDICINA.
Place of preparation: DPTO. DE MORFOLOGÍA Y BIOLOGÍA CELULAR U. DE OVIEDO.

Summary: We studied 24 patients with adenocarcinoma nasosinusal by comparative genomic hybridization (HGC). The HGC is the hybridization of DNA from healthy tissue and tumor, marked with different fluorochromes on metaphases normal. Subsequently, the results are studied by special digital image analysis. All the patients studied were male, 75% with exposure to wood dust for a mean of 25 years. The clinic was starting in approximately 88% of them nasal respiratory failure. The histological studies showed a 100% rate mucoalveolar. In all cases, physical examination was performed under local or general anesthesia with making biopsy for histological studies. The study was performed radiographic image associated with CT MRI in 4 of them. All of them were performed surgery with curative intent, involving radiotherapy in 67%. In subsequent revisions, it was local recurrence in 67% of patients, of whom 38% received palliative treatment yel 62% surgery rescue, a partner in the 60% of them to radiotherapy. Overall survival was 48.45% at 5 years. The study by HGC showed in all cases and gains or losses and Gross deletions in 62.5% of cases additions. The gains were found most frequently in: 7qll (70.8%), 8qll (66.6%), 7qll-21 YX (58.3%), 19p Y20q (50%), 18pll Y19 (45.8% ), 5p13-11, 8qll-22, 12qll-13 (41.6%) Y3q26-27 (37.5%) and losses 18q22-23 (75%), 8p23 (66.6%), 8p23-22 (58.3%), 8p23-21 and 17p13 (37.5%), 5q31-35 And 17p (33.3%) and 18q And 5q (25%). Besides earnings, 65% of patients are particularly additions: Xq13 (29.2%), Xq12 (20.8%), Xq23 and Xq25 (16.6%) and 7qll, l2p13, 20qll, and Xq (12.5%). In 25% of patients were seen training isocromosomas, the most frequent 5p / 5q (20.8%), 8q / 8p (12.5%) Y17q / 17p (8.3%). The HGC to identify chromosomal alterations present in adenocarcinomas nasosinusales. In the near future this study is to continue the study at the genetic level that can take us to a better understanding of this ilk tumor.

Author: PEREZ HIDALGO LIVIA.
Year: 2004.
University: SALAMANCA [www.usal.es].
Place of defense: CENTRO DE INVESTIGACION DEL CANCER.
Place of preparation: MICROBIOLOGIA Y GENETICA.

Author: Codina Pascual Montserrat.
Year: 2005.
University: AUTÓNOMA DE BARCELONA [www.uab.es].
Place of defense: Facultat de Medicina.
Place of preparation: Autònoma de Barcelona.

Summary: During meiotic prophase I chromosomes counterparts joined by forming synapses bivalent and exchanged genetic material recombination. Abnormalities of the synapse and meiotic recombination are treated as two possible causes of blocking all or part of meiosis. The overall objective of this work is to study the incidence of abnormal synaptic and recombination in checks and infertile individuals to characterize different degrees of abnormalities in these processes in idiopathic infertility. Have been processed testicular biopsies of seven individuals control and thirteen infertile. The detection inmunofluorescente protein CS (SCP1 and SCP3) and places of recombination (MLH1) was first used in combination with a method of in situ hybridization with multiple fluorescent probes subteloméricas specific (stM-FISH), which permits identification of all SCs a cell in paquiteno. The regions of heterocromatina not centromérica, 9qh, 1qh, 16qh and arms short of the acrocentric chromosomes, have submitted a higher incidence of abnormalities in synaptic all individuals, indicating that they are the last regions of the genome in making synapses. The incidence of synaptic abnormalities in these areas varies between individuals, a fact explained by polymorphisms of these regions in the general population. Synaptic Abnormalities in other areas, those that affect several CSs in the same kernel or those present at the stadium late paquiteno could indicate a severe impairment of the synapses. The CSs of chromosomes 15 and 21 are associated most frequently to two sex chromosomes possibly because of homology between regions heterocromáticas of these chromosomes and chromosome Y. The analysis of meiotic recombination has shown that recombination in the XY pair can be an indicator of the overall frequency of recombination and the progression of meiosis. The results confirm that a lower frequency of recombination may increase the risk of univalentes at metaphase I and interindividual differences in the frequency could explain the variability in the frequency of aneuploidies in human sperm. The results of distribution points MLH1 in each CS and the distances between points MLH1 adjacent has allowed us to propose a model of how these points are distributed along the IC. Analysis of the length of CS has shown that each of the arms of CS, independently of the other, can vary on their length compared to the relative length of chromosomes mitóticos. This paper shows that the length of this variation may reflect on the amount of fiber compact and non-compact chromatin present in the area. Finally, the observation of a cell in tetraploid paquiteno stadium, possibly caused by endoreduplicación showed that the synapse and meiotic recombination may occur in these cells in humans. Moreover, suggests that these cells are another potential source of sperm diploids. During the course of this study has been characterized citogenéticamente a reorganization of the Y chromosome by FISH probes specific for this chromosome in one individual azoospérmico. It has been determined that this individual is carrying a isocromosoma dicéntrico Yq (p11.32) in mosaic.

Author: BLEIN SÁNCHEZ DE LEÓN ANTONIO MARÍA.
Year: 2005.
University: ZARAGOZA [www.unizar.es].
Place of defense: FACULTAD DE VETERINARIA.
Place of preparation: FACULTAD DE VETERINARIA.

Summary: Safety and health are primary values for the individual. Both individually, as at the social level. Just as professional activity is often source of satisfaction and personal fulfillment, it can also be a source of injury to health. The current situation in this area is marked by the promulgation in 1995 of the Law on Prevention of Accidents at Work, which transposes the Framework Directive of the European Union. Stresses such legislation especially in the new perspective from which to address this issue, which is to address the problems before they occur, ie the avoidance. In a word, preventable. Another major development that brings this Act is the inclusion in the scope of public institutions and, therefore, of the University, being people in their Faculties pilot and especially in its laboratories, which are subject to a most at risk. Thus, this thesis examines the current situation regarding preventive Genetics Laboratories in Spain and suggest measures to overcome its deficiencies. As previous work examines the Clinical Diagnostic Laboratories teachers. They also do the study toilet of a dangerous substance often used in both types of labs, acrylamide. The methodology followed to know the situation in preventive teaching laboratories of clinical diagnosis is developing a survey, send and analyze the responses received. This survey, which consists of 100 questions closed, has five sections: the building, staff, equipment, materials and management agents. The survey was sent to 108 teaching laboratories for clinical diagnosis throughout Spain, for the secondary schools of specialty "Clinical Diagnostic Laboratories." Analizadas responses, the major deficiencies and the improvement measures being proposed are: = Lack of physical space: reducing the number of students per group and increase collections. = Emergency Plan ineffective: develop and maintain an operational emergency plan. = Lack of information on chemical agents: The request suppliers Sheet Product safety and inform users. As for the survey methodology Genetics Laboratories is very similar to the previous one. It also uses the survey, which has the same points, although in this case, he added four questions. It was sent to 125 laboratories Genetics in Spain. From the responses received are deducted major deficiencies preventive these laboratories. Known them in this study are proposed improvement measures timely. Among the most notable are: Design = no specific Laboratory for Genetics: Participation of scientific equipment with the designer. = Lack of emergency material (First Aid and spills and leaks): Providing laboratory of equipment = unskilled personnel in the handling of material for emergencies, to train staff in handling this material. = Biological Agents. Lack of information about how dangerous and mishandling: Find out about the security classification of biological agents which are manipulated and manipulation of the same in containment areas, corresponding to their level of dangerousness. With regard to hygienic study of acrylamide, a carcinogen, identify stages of risk in their use and assesses their risk under conditions described by the methodology PV2004, OSHA. Samples are taken by suction pump and pipe support absorbent. It is concluded that there is a risk toilet at the stage of heavy and proposes a number of preventive measures to eliminate or reduce the risk, foremost of which 8 are is ad 3b0 quirir acrylamide already dissolved, thus eliminating the heavy phase. The main conclusion of this work is that it is necessary to develop, implement and maintain at the Genetics Laboratory, a Management System for the Prevention of Risks to guarantee people their safety and health.