Doctor of Philosophy / Abstract Neurodegenerative disorders are a diverse group of disorders that affect specific subsets of neurons. Motor neuron diseases, neurodegenerative disorders of motor neurons, are seen commonly as sporadic cases and less frequently as familial disease forms. The familial forms show genetic and phenotypic heterogeneity. Clinically motor neuron diseases may be seen as rapidly progressive disorders like amyotrophic lateral sclerosis, ALS or slowly progressive disorders like hereditary motor neuropathies, HMN. The only proven causes for motor neuron diseases are gene mutations that lead to motor neuron degeneration in familial disease forms. Only some of these genes have been identified and have contributed greatly to our understanding of the neurobiology of familial and sporadic disease forms. Identification of additional disease causing genes would help enhance our knowledge of the pathophysiological mechanisms underlying all forms of motor neuron disorders, which would lead to early diagnoses, effective prophylaxis and efficient therapies for these disorders. This study aimed to find gene mutations that cause rapid and slowly progressive familial motor neuron disorders in Australian families and to determine their relevance to sporadic forms of motor neuron disease. The familial forms of ALS show reduced disease penetrance, that is, not all gene mutation carriers manifest the disease. This study examines ALS penetrance in a group of Australian families. The most frequently observed mutations in ALS families are cytosolic superoxide dismutase/SOD1 gene mutations. In a collection of ALS families in our centre, families without the common SOD1 gene mutations were genotyped for other ALS genes and loci and studied using genetic linkage and haplotype analyses. Studies in a large Australian ALS family further confirmed genetic heterogeneity in non-SOD familial ALS, all known autosomal dominant ALS genes and chromosomal loci were excluded as cause of disease in this family. Such families can be studied further to identify additional disease genes and loci mapped in other ALS families. These families represent powerful resources for identification of additional ALS genes. Identifying the pathogenic genes in families with reduced disease penetrance may be more relevant to sporadic forms of disease. dHMN is a chronic neurodegenerative disorder predominantly affecting motor neurons. In a large Australian dHMN family, all the known dHMN genes and chromosomal loci were excluded as cause of disease. A genome wide microsatellite screen was performed in this family and genetic linkage was established to a novel 12.98 Mb locus on chromosome 7q34.2-q36. Candidate genes in this large interval will be screened based on their function and expression profile. Identification of a new dHMN locus provides the basis for future identification of a novel gene involved in motor neuron degeneration. Genes in dHMN have been shown to be pathogenic in ALS and Charcot Marie Tooth syndromes. The new locus for dHMN mapped in this project would lead to identification of a novel dHMN gene, which may elucidate the pathogenesis underlying a wide range of neurodegenerative disorders.

Due to the costly and technically challenging nature of genetic testing, methods have been developed to target more specifically those who are at increased risk of carrying the Hereditary Non-Polyposis Colorectal Cancer (HNPCC) mutation. HNPCC is an inherited colorectal cancer syndrome. Testing of tumour material (which has previously been removed during surgery) for features of HNPCC has been found to be an effective and economic method of identifying those at higher risk of having a mutation. Only those at higher risk of having a mutation will undergo genetic testing. This practice of “tumour testing” has become widespread. / There is currently no clarity about requirements for consent prior to testing of stored tumour tissue. The person giving consent to tumour testing does not always have an appointment with a genetics service prior to giving consent. This can be contrasted to genetic testing on blood samples where laws and guidelines state that informed consent is required prior to genetic testing and that comprehensive genetic counselling and support should be provided as part of this process. Protocols for genetic testing have been developed as a result of extensive research around the impact and implications of genetic testing. / Consumer opinion and participation through research is an important aspect of health policy and guideline development. Accordingly the purpose of this study was to contribute to such development by gaining insight into the experiences, understandings, decision making processes and opinions of those who had given consent to have their own or their relatives tumour tested. Seventeen people who had given consent for tumour testing either for themselves, or on behalf of a deceased relative were recruited through a Familial Cancer Centre and in-depth interviews conducted. The interviews were transcribed and analysed using thematic analysis. / Some participants had no memory of consenting to tumour testing. Others remembered basic concepts. Negative implications of testing were unknown or viewed as unimportant. Participants did not understand the difference between tumour testing and germline testing. Despite lack of memory or understanding participants did not want additional or more detailed pre-test information although they did want more follow-up and support after receipt of results. The decision to consent to testing was made as soon as participants were informed of the availability of tumour testing - the major reason being to provide information for the family that would aid in cancer prevention. Participants were more concerned with accessibility to testing than pre test information and counselling. / Findings in this study indicated participants made decisions heuristically rather than systematically and this as well as participants’ opinions and other decision-making research has implications for the traditional view of informed consent around genetic related decisions. This in turn has implications for policy and guidelines in the area. Implications for current practise as a result of findings from this study include ensuring participants understand negative implications of testing and follow up and support of those with negative as well as positive results to tumour testing.

In dieser Arbeit verbinden wir die Theorie der Quasi-Ordnungen mit der Theorie der Algorithmen einiger kombinatorischer Objekte. Zuerst entwickeln wir die Theorie der Wohl-Quasi-Ordnungen, WQO, im Zusammenhang zur maximalen Komplexität. Dann geben wir ein allgemeines 0-1-Gesetz für erbliche Eigenschaften, das Auswirkungen für die mittlere Komplexität hat. Dieses Ergebnis für mittlere Komplexität wird auf die Klasse der endlichen Graphen, versehen mit der Relation ``induzierter Subgraph'', angewendet. Wir erhalten, daß eine große Klasse von Problemen, welche z.B. Perfektheit umfaßt, Algorithmen mit im Mittel konstanter Laufzeit haben. Dann zeigen wir, indem wir ein Ergebnis von Damaschke für Cographen veralgemeinern, daß die Klassen der endlichen Ordnungen bzw. Graphen mit beschränktem Dekompositionsdurchmesser bzgl. der Relation ``induzierte Subordnung'' bzw. ``induzierter Subgraph'' WQO sind. Dies führt uns zu linearen Erkennungsalgorithmen für alle erblichen Eigenschaften über diesen Objekten. Unser Hauptresultat ist dann, daß die Menge der endlichen partiellen Ordnungen eine Wohl-Quasi-Ordnung bzgl. einer gewissen Relation &leq; , der sogenannten Ketten-Minor-Relation, ist. Um dies zu beweisen, führen wir eine verwandte Relation auf endlichen formalen Sprachen ein, die die gleiche Eigenschaft hat. Als Folgerung erhalten wir, daß jede Eigenschaft, die erblich bzgl. &leq; ist, einen Test in <em>O(|P|^c)</em> Zeit zuläßt, wobei $c$ von der Eigenschaft abhängt. Dieser Test läßt sich leicht parallelisieren. Auf einer parallelen Maschine (\CRCW\ \PRAM) kann er so implementiert werden, daß er konstante Zeit auf <em>O(|P|^c)</em> Prozessoren benötigt.

The domestic dog, Canis familiaris, has over 450 naturally occurring inherited diseases. Over half of these diseases are clinically similar to human diseases making the dog an excellent model in which to study human hereditary diseases. Alport syndrome (AS), a group of heterogeneous, hereditary renal diseases, is one example of such a human disease. The disease is transmitted in three fashions: X-linked, autosomal recessive, and autosomal dominant. AS is caused by mutations in COL4α3, COL4α4 or COL4α5, all members of the type IV collagen family. The proteins products of these genes along with those of the other type IV collagen family members (COL4α1, COL4α2, and COL4α6) are structural components of basement membranes throughout the body. This dissertation describes the measurement of mRNA transcripts in two canine models of AS: a mixed breed model of X-linked AS (XLAS) and the English Cocker Spaniel (ECS) model of autosomal recessive AS (ARAS). The work done revealed a decrease in COL4α4 transcripts. The similarity between the decrease of COL4α5 in the XLAS model and that for COL4α4 in the ARAS model lead to the investigation of COL4α4 as the gene harboring the mutation causative for ARAS in the ECS. Upon sequencing COL4α4, the causative mutation was determined to be an A to T transversion in exon 3. To provide an in vitro model to study type IV collagens, a protocol was designed and experimentally validated to isolate and culture canine Sertoli cells. Canine testes cells were isolated and cultured. Cells were verified as Sertoli cells through positive identification of both SOX9 and Clusterin B proteins, along with sequence verification of SOX9 transcripts. This in vitro model provides a tool to further study the type IV collagens. Overall, the research described herein lead to the identification of the mutation causative for ARAS in the ECS. With this knowledge a genetic test was developed to test for the disease. This research also provided valuable information about the transcript levels of type IV collagens in two models of AS, and provided a novel model in which to study the type IV collagens further.

Les paraplégies spastiques héréditaires (PSH) sont des maladies cliniquement et génétiquement hétérogènes, qui se manifestent par la présence de signes pyramidaux (spasticité, réflexes myotatiques vifs et diffusés) et d’un déficit moteur des membres inférieurs. On distingue des formes pures et complexes de PSH, ces dernières étant associées à la présence de signes additionnels tels que troubles cognitifs, neuropathie périphérique, signes cérébelleux, etc. Les mécanismes physiopathologiques des PSH sont également hétérogènes, incluant une anomalie du transport axonal (SPG3A, SPG4, SPG10, SPG20), du métabolisme mitochondrial (SPG7, SPG13), une anomalie de la formation de la myéline (SPG1) ou un dysfonctionnement du développement neuronal (SPG2). Elles peuvent se transmettre selon le mode autosomique dominant (AD), récessif (AR), ou récessif lié au chromosome X. Actuellement, 13 loci dont 9 gènes de PS-AD sont connus, mais seulement 5 gènes responsables de PS-AR ont été identifiés, alors que 14 loci sont connus. De par leur hétérogénéité clinique, génétique et physiopathologique, les PSH sont encore des maladies mal connues. Une meilleure connaissance du phénotype associé à chaque locus/gène permettrait aux cliniciens de mieux orienter les analyses moléculaires pour un diagnostic rapide. L’établissement de corrélations génotype-phénotypes et de la fréquence des gènes impliqués dans les PSH permettrait tant aux cliniciens qu’aux biologistes de cibler les gènes, les exons à analyser ou les mutations à rechercher en priorité. L’identification des mécanismes physiopathologiques des mutations est une première étape vers des études fonctionnelles et des traitements spécifiques. Nous avons montré que la forme de PS AD liée à des mutations dans le gène SPG3A était caractérisée par un début très précoce, avant l’âge de 10 114 ans. Cette forme en générale pure de PS peut se compliquer, notamment par une neuropathie périphérique ou un syndrome cérébelleux après une longue durée d’évolution de la maladie. Ces résultats permettent d’orienter les analyses moléculaires vers le gène SPG3A avant le gène SPG4, devant tout patient qui a débuté la maladie précocement, quelque soit le tableau clinique. Nous avons montré que les mutations dans le gène SPG3A, dont les mutations récurrentes p.R239C et p.R495W dans les exons 7 et 12 peuvent apparaître de-novo, justifiant l’analyse de ce gène chez des patients isolés. Nous avons étendu le phénotype des PS AD liées à des mutations dans le gène SPG4, qui doit être analysé chez les patients présentant une PS associée à un retard mental sans malformation cérébrale. De plus, nous avons montré que les délétions de ce gène ne sont pas rares, atteignant une fréquence de 20% chez les patients présentant une PS-AD sans mutation retrouvée par DHPLC. Ceci entraîne un changement des stratégies d’analyses moléculaires utilisées chez les patients atteints de PS, avec l’instauration systématique d’un MLPA chez chaque patient. Nous avons précisé le tableau clinique des paraplégies spastiques AR liées aux loci SPG26 et 27. Nous avons réduit l’intervalle génomique de ces loci. L’identification d’autres familles liées à ces loci permettra de réduire encore plus leurs intervalles génomiques, voire d’identifier les gènes responsables de ces maladies.

The domestic dog, Canis familiaris, has over 450 naturally occurring inherited diseases. Over half of these diseases are clinically similar to human diseases making the dog an excellent model in which to study human hereditary diseases. Alport syndrome (AS), a group of heterogeneous, hereditary renal diseases, is one example of such a human disease. The disease is transmitted in three fashions: X-linked, autosomal recessive, and autosomal dominant. AS is caused by mutations in COL4α3, COL4α4 or COL4α5, all members of the type IV collagen family. The proteins products of these genes along with those of the other type IV collagen family members (COL4α1, COL4α2, and COL4α6) are structural components of basement membranes throughout the body. This dissertation describes the measurement of mRNA transcripts in two canine models of AS: a mixed breed model of X-linked AS (XLAS) and the English Cocker Spaniel (ECS) model of autosomal recessive AS (ARAS). The work done revealed a decrease in COL4α4 transcripts. The similarity between the decrease of COL4α5 in the XLAS model and that for COL4α4 in the ARAS model lead to the investigation of COL4α4 as the gene harboring the mutation causative for ARAS in the ECS. Upon sequencing COL4α4, the causative mutation was determined to be an A to T transversion in exon 3. To provide an in vitro model to study type IV collagens, a protocol was designed and experimentally validated to isolate and culture canine Sertoli cells. Canine testes cells were isolated and cultured. Cells were verified as Sertoli cells through positive identification of both SOX9 and Clusterin B proteins, along with sequence verification of SOX9 transcripts. This in vitro model provides a tool to further study the type IV collagens. Overall, the research described herein lead to the identification of the mutation causative for ARAS in the ECS. With this knowledge a genetic test was developed to test for the disease. This research also provided valuable information about the transcript levels of type IV collagens in two models of AS, and provided a novel model in which to study the type IV collagens further.

Lynch syndrome (LS) is the most prevalent cause of hereditary colorectal cancer (CRC) and confers high risks for several other types of cancer. Universal tumor screening (UTS) of all newly diagnosed patients with CRC can improve LS identification and decrease associated morbidity and mortality among patients and family members. However, for UTS to be effective, patients who screen positive must pursue genetic counseling and confirmatory germline testing (i.e., high patient reach). The purposes of this study were to characterize UTS programs, identify barriers and facilitators to implementation, document whether there have been negative outcomes, and determine institutional and implementation conditions that are associated with high and low patient reach. Using two conceptual frameworks, RE-AIM and Consolidated Framework for Implementation Research, a baseline survey was conducted of 25 representatives from different institutions performing UTS. Descriptive statistics were used to illustrate similarities and differences among programs. A multiple-case study was then conducted by extracting data from surveys and interviews of representatives from 15 different institutions where UTS programs had been operational for over 6 months and where aggregated patient outcome data were available. Qualitative comparative analysis was performed to make systematic cross-case comparisons and identify conditions uniquely associated with high or low patient reach. Data were triangulated to create models explaining how UTS implementation and system-level factors influence patient reach. Few patient concerns or negative outcomes were reported. UTS procedures and patient reach were highly variable. All 5 high-reach (H-R) centers have genetics professionals disclose positive screening results and either do not require a referral from another health care provider or have streamlined the referral process. Although 2 of the 5 mid-reach (M-R) centers also share these conditions, they have a less automated follow-up procedure and report difficulty contacting patients as a barrier. Both of the academic institutions with low patient reach (L-R) did not receive patient information that would allow them to follow-up on positive screening results. The three non-academic L-R institutions reported a high proportion of challenges to facilitators during implementation and did not have genetic professionals disclose positive screening results to patients. Implementing a combination of procedures to streamline UTS protocols and procedures, eliminate barriers to patient follow-through after a positive tumor screen, and incorporate a high level of involvement of genetic professionals in contacting patients and disclosing screening results are expected to lead to improvement in patient reach

O καρκίνος του μαστού αποτελεί την δεύτερη πιο συχνή μορφή καρκίνου που απαντάται και στα δύο φύλα ενώ είναι συνιστά την πιο συχνά εμφανιζόμενη μορφή καρκίνου στις γυναίκες καθώς και την πρώτη αιτία θανάτου στο γυναικείο φύλο. Η γενετική ανάλυση του κληρονομικού καρκίνου έχει ενταχθεί τα τελευταία χρόνια και αποτελεί σημαντικό μέρος της κλινικής πράξης, καθώς όλο και περισσότεροι ασθενείς ελέγχονται για την ύπαρξη γαμετικών μεταλλάξεων στα υψηλής διεισδυτικότητας γονίδια BRCA1 και BRCA2. Προκειμένου να μελετήσουμε την συνεισφορά των γονιδίων BRCA1 και BRCA2 στην εμφάνιση καρκίνου μαστού στον ελληνικό πληθυσμό εξετάστηκαν 200 άτομα που παρουσίαζαν σημαντικό ατομικό ή/και οικογενειακό ιστορικό καρκίνου του μαστού ή/και των ωοθηκών. Έτσι, στην περίπτωση του γονίδιου BRCA1 βρέθηκαν 13 διαφορετικές παθογόνοι μεταλλάξεις σε 29 από τις ασθενείς (14.5%) ενώ για το γονίδιο BRCA2 αναλύθηκαν συνολικά 156 ασθενείς (155 γυναίκες και 1 άνδρας) και μεταλλάξεις ανιχνεύθηκαν σε 8 γυναίκες (5.2%) και 1 άνδρα (100%). Παράλληλα έγινε προσπάθεια χαρακτηρισμού του φάσματος μεταλλάξεων του μετρίου διεισδυτικότητας γονιδίου RAD51C σε ελληνικές οικογένειες. Η ανάλυση αυτή πραγματοποιήθηκε σε 87 ασθενείς όμως δεν ανιχνεύθηκε κάποια παθογόνος μετάλλαξη σε κάποιον ασθενή. Επιπρόσθετα, πραγματοποιήθηκε η ανίχνευση μεγάλων γονιδιακών αναδιατάξεων στα γονίδια BRCA1 και BRCA2 με την βοήθεια τριών τεχνικών ανίχνευσης: την τεχνική της ανίχνευσης γονιδιακών αναδιατάξεων με χρήση διαγνωστικών εκκινητών για τις πιο συχνές γονιδιακές αναδιατάξεις του γονιδίου BRCA1 στον ελληνικό πληθυσμό (δύο απαλειφές του εξωνίου 20, μία απαλειφή των εξονίων 23 και 24 και τέλος μια απαλειφή του εξονίου 24), την τεχνική της πολλαπλής και ποσοτικής αλυσιδωτής αντίδρασης της πολυμεράσης μικρών φθοριζόντων τμημάτων (QMPSF) για το γονίδιο BRCA1 και την τεχνική της πολλαπλής ενίσχυσης τμημάτων DNA μέσω ιχνηθετών (MLPA®) τόσο για το γονίδιο BRCA1 όσο και για το γονίδιο BRCA2. Η τεχνική της ανίχνευσης με την χρήση διαγνωστικών εκκινητών εφαρμόστηκε σε 200 ασθενείς με καρκίνο μαστού ή/και ωοθηκών και ανιχνεύθηκαν 15 ασθενείς που έφεραν κάποια από τις συχνότερες γονιδιακές αναδιατάξεις του γονιδίου BRCA1 (7.5%). Αντίθετα, με την τεχνική του QMPSF και του MLPA δεν ανιχνεύθηκε κάποια γονιδιακή αναδιάταξη στα BRCA1/2 στους συνολικά 24 ασθενείς που εξετάστηκαν. Επιπλέον, στα πλαίσια της παρούσας διατριβής πραγματοποιήθηκε η ανάλυση 403 γυναικών με τριπλά αρνητικό καρκίνο του μαστού ανεξαρτήτως οικογενειακού ιστορικού και ηλικίας εμφάνισης της νόσου. Κατά την ανάλυση αυτή ελέγχθηκαν συγκεκριμένα εξόνια καθώς και γονιδιακές αναδιατάξεις του BRCA1. Μεταλλάξεις ανιχνεύθηκαν σε 65 από τις ασθενείς αυτές (16%). Στα πλαίσια της παρούσας διατριβής πραγματοποιήθηκε ανάλυση απλοτύπου προκειμένου να αποδειχθεί ότι η απαλειφή των εξονίων 23 και 24 αποτελεί ελληνική ιδρυτική μετάλλαξη. Για το σκοπό αυτό αναλύθηκε ο απλότυπος σε 21 οικογένειες που έφεραν την συγκεκριμένη γονιδιακή αναδιάταξη με την βοήθεια της τεχνικής των πολυμορφικών δεικτών επαναλήψεων μικροδορυφορικού DNA. Η ανάλυση απλοτύπου κατέδειξε ότι 8 από 10 γενετικούς τόπους είναι κοινοί μεταξύ των ατόμων που φέρουν την απαλοιφή επιβεβαιώνοντας έτσι την υπόθεση ότι η απαλειφή αυτή αποτελεί ιδρυτική μετάλλαξη του ελληνικού πληθυσμού. Ακολούθως, μελετήθηκε η συνεισφορά και άλλων γονιδίων στην προδιάθεση για καρκίνο μαστού και ωοθηκών και πραγματοποιήθηκε ανάλυση 21 γονιδίων (BRCA1, BRCA2, CHEK2, PALB2, BRIP1, TP53, PTEN, STK11, CDH1, ATM, BARD1, MLH1, MRE11, MSH2, MSH6, MUTYH, NBN, PMS1, PMS2, RAD50, RAD51C) με την χρήση τεχνολογίας αλληλούχισης επόμενης γενεάς. Για το σκοπό αυτό αναλύθηκαν 42 ασθενείς με σοβαρό ιστορικό καρκίνο μαστού ή/και ωοθηκών, οι οποίες είχαν βρεθεί αρνητικές για μεταλλάξεις στα γονίδια BRCA1 & 2. Κατά την ανάλυση αυτή βρέθηκαν μεταλλάξεις σε 11 ασθενείς (26.2%). Ακόμα, πραγματοποιήθηκε εξομική αλληλούχιση σε μια ασθενή, η οποία παρουσίαζε βαρύτατο ατομικό και οικογενειακό ιστορικό και είχε βρεθεί αρνητική για μεταλλάξεις σε 21 γονίδια (BRCA1, BRCA2, CHEK2, PALB2, BRIP1, TP53, PTEN, STK11, CDH1, ATM, BARD1, MLH1, MRE11, MSH2, MSH6, MUTYH, NBN, PMS1, PMS2, RAD50, RAD51C). Η αλληλούχιση αυτή πραγματοποιήθηκε από την εταιρεία BGI. Συνολικά ανιχνεύθηκαν 39.762 πολυμορφισμοί ενός νουκλεοτιδίου (SNPs) και 1,646 μικρές ενθέσεις/απαλειφές (InDels) σε ολόκληρο το γονιδίωμα της ασθενούς. Μετά από ανάλυση των αποτελεσμάτων αυτών καταλήξαμε σε 12 παραλλαγές που αποτελούν ενδεχομένως πιθανά παθογόνα αλληλόμορφα. / Breast cancer is the second most common cancer in both sexes while it is the most frequent cancer as well as the first cause of death in women. The genetic testing of hereditary cancer is part of the everyday clinic as the number of patients that is checked for germline mutation in BRCA1 and BRCA2 is continuously increasing. In order to study the contribution of the high penetrance genes BRCA1 and BRCA2 in breast cancer in Greece 200 patients with severe history of breast and/or ovarian cancer were screened. In BRCA1 13 different pathogenic mutations were found in 29 patients (14.5%) while in BRCA2 156 patients were screened (155 female and 1 male) and pathogenic mutations were identified in 8 female (5.2%) and 1 male patients (100%). At the same time, we tried to characterize the mutation spectrum of the medium penetrance gene RAD51C in Greek families. For this purpose, we screened 87 patients but no mutations was found. In addition, the identification of large genomic rearrangements in both genes took place, using three methods: diagnostic primers were used in order to identify the 4 most common BRCA1 genomic rearrangements in Greece (two deletions in exon 20, one deletion of exons 23 and 24 and one in exon 24), the QMPSF method for the BRCA1 genomic rearrangements (Quantitative Multiplex PCR of Short Fluorescent fragments) and the MLPA method for both BRCA1 and BRCA2 genomic rearrangements (Multiplex Ligation-dependent Probe Amplification). With the first technique 200 patients with breast and/or ovarian cancer were analyzed and 15 of them were found to carry one of the most frequent BRCA1 genomic rearrangements. In the contrary, no large genomic rearrangements in neither gene was identified among the 24 patients who were screened using the two latter methods (QMPSF and MLPA). Also, we have screened 403 triple negative female patients who were diagnosed with triple-negative invasive breast cancer, independently of their age or family history, for germline BRCA1 mutations in exons where a mutation have previously been found in Greek population including the genomic rearrangements. Mutation were identified in 65 patients (16%). In this study we used haplotype analysis in order to demonstrate that the BRCA1 deletion of exons 23 and 24 constitutes a Greek founder mutation. For this purpose, we performed haplotype analysis in 21 Greek families who carry this specific genomic rearrangement using the DNA Microsatellite Repeats analysis. The haplotype analysis showed that 8 out of 10 genetic regions are common among people that carry this deletion confirming that the deletion is a Greek founder mutation. We also studied the contribution of other genes in breast/ovarian cancer predisposition by studying 21 genes (BRCA1, BRCA2, CHEK2, PALB2, BRIP1, TP53, PTEN, STK11, CDH1, ATM, BARD1, MLH1, MRE11, MSH2, MSH6, MUTYH, NBN, PMS1, PMS2, RAD50, RAD51C) using next generation sequencing techniques. We examined 42 patients with severe breast and/or ovarian cancer history that were found negative for BRCA1/2 mutations. In this analysis pathogenic mutation were found in 11 patients (26.2%). At last, exome sequencing was performed in a female patient who had severe family history and was found negative for germline mutations in 21 genes (BRCA1, BRCA2, CHEK2, PALB2, BRIP1, TP53, PTEN, STK11, CDH1, ATM, BARD1, MLH1, MRE11, MSH2, MSH6, MUTYH, NBN, PMS1, PMS2, RAD50, RAD51C). The sequencing was carried out by Beijing Genomics Institute (BGI). In total, were identified 39.762 singe nucleotide polymorphisms (SNPs) and 1.646 insertions - deletions (InDels) in the patient's exome. After the result analysis we concluded in 12 variants that could constitute possible pathogenic alleles.

Die vorliegende Untersuchung beschäftigt sich mit dem hereditären Angioödem (HAE) als seltene, erbliche Erkrankung. Beim HAE kommt es zu rezidivierenden Schwellungen an der Haut, des Larynx und der intestinalen Organe. Ziel der vorliegenden prospektiven, offenen Studie war die klinische Charakterisierung von HAE-Patienten aus dem mitteldeutschen Raum einschließlich der Erfassung und des Vergleiches der Lebensqualität (LQ). Es wurden 46 HAE-Patienten aus dem mitteldeutschen Raum um Einwilligung in die Studie gebeten. 21 selbstausgefüllte Lebensqualitätsfragebögen sowie 19 standardisierte, 20-30-Minütige Telefoninterviews und die retrospektiv erfassten Krankendaten konnten ausgewertet werden. Der Vergleich der Lebensqualität von HAE-Patienten mit der Lebensqualität von Patienten mit chronischen Erkrankungen und Hautkrankheiten mit dem SF-36 und FLQA-d erfolgte im Studienzeitraum erstmalig. Die Studie konnte die Merkmale der Erkrankung des hereditären Angioödems bei Patienten aus dem mitteldeutschen Raum aufzeigen. Zwischen den HAE-Typ I und II-Patienten bestanden Unterschiede bezüglich der Vorzeichen und der Organmanifestationen. Auf die Therapie hatten diese Unterschiede keinen Einfluss. Insgesamt zeigte sich auch nach Anwendung der Lebensqualitätsfragebögen: SF-36 und FLQA-d wie schwierig die Erfassung der Lebensqualität bei HAE-Patienten ist. Zum einen sind die Fragebögen nicht spezifisch für HAE-Patienten und zum anderen sind die Ergebnisse dieser Studie durch die kleine Gruppengröße und der einzeitigen Erfassung in der Übertragbarkeit eingeschränkt. In zukünftigen Studien sollte dem Bereich der sozialen Funktionsfähigkeit bei der Erfassung der Lebensqualität Beachtung geschenkt werden. Der im Juli 2012 von Prior et al veröffentlichte, krankheitsspezifische Lebensqualitätsfragebogens HAE-QoL (111) sollte weiterentwickelt sowie die erhobenen Daten mittels einer prospektiven Studie bezüglich der Lebensqualität vor und nach einer bestimmten Therapie überprüft werden.

Hereditary tyrosinemia type 1 (HT1) is an autosomal recessive disorder of the tyrosine degradation pathway. The defective fumarylacetoacetate hydrolase enzyme causes the accumulation of upstream metabolites such as fumarylacetoacetate (FAA), maleylacetoacetate (MAA), succinylacetone (SA) and p-hydroxyphenylpyruvic acid (pHPPA). In vitro and in vivo studies showed that the accumulation of these metabolites are detrimental to cell homeostasis, by inducing cell cycle arrest, apoptosis, and endoplasmic reticulum stress, depleting GSH, inhibiting DNA ligase, causing chromosomal instability, etc. For in vivo studies different models of HT1 were developed. Most notably was the fah deficient mouse, whose neonatally lethal phenotype is rescued by the administration of 2-(2-nitro-4-trifluoromethylbenzoyl)-1,3-cyclohexanedione (NTBC). Although, this model most closely resembles the human phenotype with elevated tyrosine levels and the development of hepatocellular carcinoma (HCC), the model is not human genome based. Both the in vitro and in vivo studies suggested that DNA repair is affected in HT1. However, it is not yet clear which DNA repair mechanisms are affected and if only protein functionality is affected, or if expression of DNA repair proteins are also affected. Characteristic of HT1 is the high prevalence of HCC and the presence of liver mosaicism. The liver mosaicism observed in HT1 patients are the result of reversion of the inherited mutation to wild-type. The general consensus is that the reversion is the result of a true back mutation. However, the mechanism underlying the back mutation is still unresolved. It was suggested that cancer develops either through a chromosomal instability mutator phenotype, a microsatellite instability mutator phenotype, or a point mutation instability mutator phenotype. In HT1 only chromosomal instability was reported. The aims of this study were to contribute to the understanding of the molecular basis of the genetic mosaicism in hereditary tyrosinemia type 1. More specifically, determine whether baseand nucleotide DNA repair mechanisms are affected and to what extent, and to determine if microsatellite instability is found in HT1. To achieve these aims, a parallel approach was followed: i.e. to develop a HT1 hepatic cell model and to use HT1 related models and HT1 patient material. To assess the molecular basis of the genetic mosaicism in HT1, the comet assay, gene expression assays, microsatellite instability assays, high resolution melting and dideoxy sequencing techniques were employed. Results from the comet assay showed that the HT1 accumulating metabolites, SA and pHPPA, decreased the capacity of cells for base- and nucleotide excision repair. Gene expression assays showed that short term exposure to SA and/or pHPPA do not affect expression of hOGG1 or ERCC1. The expression of these genes were, however, low in HT1 patient samples. Microsatellite instability assays showed allelic imbalance on chromosome 7 of the mouse genome, and microsatellite instability in the lymphocytes of HT1 patients. Although high resolution melt and sequencing results did not reveal any de novo mutations in fah or hprt1, the appearance of de novo mutations on other parts of the genome can not be ruled out. To conclude, results presented in this thesis, for the first time show that in HT1 the initiating proteins of the base- and nucleotide repair mechanisms are affected, the gene expression of DNA repair proteins are low, and microsatellite instability is found in HT1. By contributing to the elucidation of the mechanism underlying the development of HT1-associated HCC, and providing evidence for the development of a mutator phenotype, the results presented in this thesis contributes to the understanding of the molecular mechanisms underlying the genetic mosaicism in HT1. In addition to these contributions, a hypothesis is posited, which suggests that a point mutation instability (PIN) mutator phenotype is the mechanism underlying the mutation reversions seen in HT1. / Thesis (Ph.D. (Biochemistry))--North-West University, Potchefstroom Campus, 2012