Zhang Jun. / "August 2000." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (p. 109-144). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Qin, Yun. / "April 2002." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2002. / Includes bibliographical references (p. 229-254). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. Ann Arbor, MI : ProQuest Information and Learning Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

Chiu Wai Kwun Rossa. / "July 2004." / Thesis (Ph.D.)--Chinese University of Hong Kong, 2004. / Includes bibliographical references (p. 144-176). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web. / Abstracts in English and Chinese.

The discovery of fetal-derived circulating nucleic acids in maternal plasma has opened up new opportunities for non-invasive prenatal diagnosis. This non-invasive means of obtaining fetal genetic materials is safer than invasive tissue-sampling procedures, which are associated with a small but finite chance of fetal loss. Over the past decade, the detection of fetal DNA in maternal plasma has evolved from dependency on discriminative genetic markers, such as Y-chromosome-specific loci or paternally-inherited polymorphisms, to detection of circulating RNA, fetal-specific methylation or by massively parallel sequencing. Fetal-specific methylation, or fetal epigenetic marker, does not require prior knowledge of the sex or polymorphic status of the fetus and thus can be applied in essentially all pergnancies. This thesis focuses on the development of this kind of marker for non-invasive monitoring and detection of pre-eclampsia and fetal aneuploidies. / The first part of this thesis describes the use of a reported fetal epigenetic marker, RASISF1A, to measure the fetal DNA concentrations in maternal plasma of pre-eclamptic subjects versus gestational-age-matched controls. The second part of this thesis describes a systematic search for potential epigenetic markers for pre-eclampsia and the second commonest fetal aneuploidy, trisomy 18. Numerous approaches for methylation profiling are described, such as methylation-specific polymerase chain reaction (MSP), bisulfite sequencing, a mass spectrometry-based platform (the Epityper assay), and methylated DNA immunoprecipitation coupled with tiling array analysis (MeDIP-chip). Using MeDIP-chip, I selected the most promising fetal epigenetic markers on chromosome 18, and further characterised their detection in maternal plasma. The final part of this thesis describes an approach called epigenetic-genetic (EGG) chromosome dosage for the detection of trisomy 18 based on those markers. I have demonstrated that it is feasible to detect fetal trisomy 18 by analysing maternal plasma in as early as the first trimester. / This thesis illustrates different strategies for methylation profiling and presented two examples of applying DNA methylation for the non-invasive prenatal assessment of pregnancy-associated disorders and fetal chromosomal aneuploidies. I envision that a similar strategy could be developed for other pregnancy-related diseases to broaden the application of epigenetic markers in non-invasive prenatal diagnosis. / Tsui, Wai Yi. / Adviser: Y.M. Dennis Lo. / Source: Dissertation Abstracts International, Volume: 73-02, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 198-221). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

Prenatal diagnosis is an established obstetrics practice in many countries. Currently available methods to obtain fetal materials for a definitive diagnosis involve invasive procedures such as chorionic villus sampling and amniocentesis. Due to the invasive nature of the procedures, confirmatory testing is usually recommended only for pregnant women who are screened as being high risk of bearing a fetus with abnormalities. There has been an urge to develop safer alternatives in obtaining fetal genetic materials for prenatal assessment. Thus, the discovery of circulating fetal DNA in maternal plasma and serum has opened up new possibilities for noninvasive prenatal diagnosis. / The use of genetic markers such as Y chromosomal sequences from a male fetus or paternally-inherited polymorphic markers has been well-described in the literature. However, there is an obvious limitation on the use of these markers because they are gender- and/or polymorphism-dependent. This thesis focuses on the development of a universal fetal marker, namely SERPINB5 (encoding maspin), based on the intrinsic epigenetic differences between the placenta (the major contributor of fetal genetic materials in maternal plasma) and maternal blood cells (postulated to be the predominant source of cell-free DNA in the circulation). Analysis of the methylation profile of the SERPINB5 promoter in the placenta and maternal blood cells, and the development of methods and protocols to detect the differentially methylated SERPINB5 promoter molecules are described. The application of this epigenetic marker in prenatal assessment of the fetal chromosomal aneuploidy is illustrated by an epigenetic allelic ratio (EAR) approach. Basically, the ratio of a single-nucleotide polymorphism (SNP) on the placenta-derived SERPINB5 molecules is shown to be deviated in the maternal plasma from trisomic pregnancies when compared to the euploid ones. Results described in this thesis show the promising potential for the EAR approach for the noninvasive prenatal detection of fetal chromosomal aneuploidies. In addition, a novel approach for methylation analyses on the amplification and detection of restriction enzyme-digested DNA fragments will be discussed. This thesis has essentially described the evolution of a fetal epigenetic marker from basic science to potential clinical application. / Tong, Yu Kwan. / Adviser: Yuk-Ming Dennis Lo. / Source: Dissertation Abstracts International, Volume: 69-02, Section: B, page: 0953. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 149-172). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / School code: 1307.

In the first part of this thesis, two chromosome Y specific genes ( SRYand TSPY) were chosen as the molecular targets to investigate the characteristics of fetal-specific DNA fragments in maternal plasma. By employing the touch down ligation-mediated PCR coupled with cloning and sequencing, the end property and the fragment species of fetal DNA were studied. / Noninvasive prenatal detection of fetal chromosomal aneuploidies is a much sought-after goal in fetomaternal medicine. The discovery of fetal DNA in the plasma of pregnant women has offered new opportunities for this purpose. However, the fact that fetal DNA amounts to just a minor fraction of all DNA in maternal plasma makes it challenging for locus-specific DNA assays to detect the small increase in sequences derived from a trisomic chromosome. On the other hand, although the clinical applications of plasma DNA for prenatal diagnosis are expanding rapidly, the biological properties of circulating DNA in plasma remain unclear. Recently, next-generation sequencing technologies have transformed the landscape of biomedical research through the ultra-high-throughput sequence information generated in a single run. Massively parallel sequencing allows us to study plasma DNA at an unprecedented resolution and also precisely detect fetal chromosomal aneuploidies in a locus-independent way. / Our group has demonstrated the use of massively parallel sequencing to quantify maternal plasma DNA sequences for the noninvasive prenatal detection of fetal trisomy 21. In the second part of this thesis, the clinical utility of this new sequencing approach was extended to the prenatal detection of fetal trisomy 18 and 13. A region-selection method was developed to minimize the effects of GC content on the diagnostic sensitivity and precision for the prenatal diagnosis of trisomy 13. To facilitate the next-generation sequencing-based maternal plasma DNA analysis for clinical implementation, two measures, i.e., lowering the starting volume of maternal plasma and barcoding multiple maternal plasma samples, were investigated. / Taken together, the results presented in this thesis have demonstrated the clinical utility of massively parallel sequencing of maternal plasma DNA and have also provided us a better understanding of the biology of circulating DNA molecules. / The third part of this thesis focuses on the massively parallel paired-end sequencing of plasma DNA. By analyzing millions of sequenced DNA fragments, the biological properties of maternal plasma DNA were elucidated, such as the size distribution of fetal-derived and maternally-contributed DNA molecules and the potential effect of epigenetic modification on DNA fragmentation. Moreover, the plasma DNA from hematopoietic stem cell transplant patients was characterized by paired-end sequencing approach. These sequencing data not only confirmed the predominant hematopoietic origin of cell-free DNA but also revealed the size difference between hematologically-derived and other tissue-derived DNA molecules in plasma. / Zheng, Wenli. / Adviser: Lo Yu Ming Dennis. / Source: Dissertation Abstracts International, Volume: 73-03, Section: B, page: . / Thesis (Ph.D.)--Chinese University of Hong Kong, 2010. / Includes bibliographical references (leaves 261-275). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

1997年，胎兒DNA被首次證實存在於母體血漿中。這一發現促進了無創產前診斷技術的發展。由於孕婦血漿中含大量來自母體的背景DNA，這給針對胎兒特異性DNA序列以外的產前診斷變得有挑戰性。近期開發的大規模平行測序技術把DNA定量精度提升到了一個空前的水平。本團隊已證實這一技術可應用於對胎兒染色體非整倍體和對胎兒全基因組的檢測。由於目前平行測序的費用仍相當昂貴，目標性測序技術可提高目標區域的數據比例從而降低測序成本。 / 在論文第一部分，本人論述了目標性測序在母體血漿DNA應用的可行性。本實驗採用雜交型富集技術對X染色體的外顯子進行富集。我們用平行測序比較了經由和未經富集處理的樣本。對比發現，經富集處理的樣本在目標區域的平均測序深度是未經富集處理樣本的213倍。目標區域的母體和胎兒DNA分子的富集程度相當。經富集處理後，目標區域的胎兒特異性等位基因的檢測率從3.5%提升至95.9%。 / 在論文第二部分，本人論述了目標性測序對胎兒21三體無創產前診斷的應用價值。我們對7，13，18和21號染色體上的單核苷酸多態性位點進行目標性測序。目標性測序數據顯示，在父源性21三體的樣本中，21號染色體上的胎兒特異性等位基因與共有性等位基因的比值上升約2倍。而在母源性21三體的樣本中，這一比值則下降約11%。本人採用電腦模擬實驗探討胎兒DNA濃度，有效等位基因數量和測序深度對檢測準確率的影響。 / 在論文第三部分，本人論述了目標性測序對胎兒單基因疾病無創產前診斷的應用。針對兩個需進行β地中海貧血產前診斷的家庭，我們對其β球蛋白基因進行目標性測序。我們用數字PCR技術推導了父母親β球蛋白基因區域的單倍型。經過相對性單倍型劑量分析，兩個胎兒的β地中海貧血遺傳狀況均得到了正確的推斷。其中一對夫婦位於致病區域的單倍型結構相近。 / 鑒於目標性測序技術可降低測序成本和提高目標序列的通量，其在血漿DNA的應用將有助於平行測序技術在無創性產前診斷、癌症診斷和移植監控等分子診斷學領域的發展。 / The presence of fetal DNA in the cell-free plasma of pregnant women was first reported in 1997. This discovery has facilitated the development of noninvasive prenatal diagnosis. The coexistence in maternal plasma of a minor population of fetal DNA among a major background of maternal DNA has posed challenges for extending noninvasive prenatal diagnostic applications that require analytical information beyond the detection of fetus-specific DNA sequences. The recent availability of massively parallel sequencing has enhanced the precision of DNA quantification to an unprecedented level. Our group has demonstrated the application of massively parallel sequencing in noninvasive prenatal diagnosis of chromosomal aneuploidies, as well as genome-wide fetal whole genome sequencing and mutational profiling. While the current costs of massively parallel sequencing are relatively expensive, targeted massively parallel sequencing may enhance the cost-effectiveness compared with the non-targeted approach because it increases the proportion of informative data from the regions-of-interest. / In the first part of this thesis, I have demonstrated the feasibility of targeted massively parallel sequencing in maternal plasma DNA. In this proof-of-principle study, hybridization-based target enrichment was used to enrich exons on chromosome X. Plasma DNA libraries with and without target enrichment were analyzed by massively parallel sequencing. For the targeted regions, the mean sequencing depth of the enriched samples was 213-fold higher than that of the non-enriched samples. Maternal and fetal DNA molecules were enriched to similar extents within the targeted regions. With target enrichment, the detection rate of fetus-specific alleles within the targeted regions increased from 3.5% to 95.9%. / In the second part of this thesis, I have demonstrated the potential application of targeted massively parallel sequencing of plasma DNA for noninvasive prenatal diagnosis of trisomy 21 using an allelic ratio approach. Targeted sequencing was used to enrich single nucleotide polymorphism loci on chr7, chr13, chr18 and chr21. The targeted sequencing data showed that the ratio between fetus-specific and shared alleles increased by approximately 2-fold on chr21 in a paternally-derived trisomy 21 case, and decreased by approximately 11% on chr21 for maternally-derived trisomy 21 cases. I have also used computer simulation to determine the impact of fractional fetal DNA concentration, number of informative alleles and sequencing depth on the detection accuracy. / In the third part of this thesis, I have demonstrated the feasibility of targeted massively parallel sequencing of maternal plasma DNA for noninvasive prenatal diagnosis of monogenic diseases. Targeted sequencing was used to enrich the β-globin gene region in two families undergoing prenatal diagnosis for β-thalassemia. Parental haplotypes of the β-globin gene region were deduced via digital polymerase chain reaction. Relative haplotype dosage analysis was performed successfully to determine the β-thalassemic status for the fetuses, including one family in which the parents had similar haplotype structures in the disease-causing region. / Because of its potential to save costs and increase throughput, targeted sequencing may catalyse the translation of massively parallel sequencing based molecular diagnostics into many fields, including noninvasive prenatal diagnosis, cancer diagnostics and transplantation monitoring. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Liao, Jiawei. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 147-155). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese. / ABSTRACT --- p.i / ACKNOWLEDGEMENTS --- p.vi / PUBLICATIONS --- p.vii / CONTRIBUTORS --- p.viii / TABLE OF CONTENTS --- p.ix / LIST OF TABLES --- p.xiii / LIST OF FIGURES --- p.xiv / LIST OF ABBREVIATIONS --- p.xvi / Chapter SECTION I : --- BACKGROUND --- p.1 / Chapter CHAPTER 1: --- Cell-free fetal DNA and targeted massively parallel sequencing --- p.2 / Chapter 1.1 --- Cell-free fetal DNA in maternal plasma --- p.2 / Chapter 1.2 --- NIPD by qualitative analysis --- p.3 / Chapter 1.2.1. --- Fetal sex assessment --- p.4 / Chapter 1.2.2. --- RHD genotyping --- p.5 / Chapter 1.2.3. --- Other implementations --- p.5 / Chapter 1.3 --- NIPD by quantitative analysis --- p.6 / Chapter 1.3.1. --- NIPD of chromosomal aneuploidies --- p.6 / Chapter 1.3.2. --- NIPD of autosomal recessive monogenic diseases --- p.8 / Chapter 1.4 --- Massively parallel sequencing of maternal plasma --- p.9 / Chapter 1.4.1. --- Massively parallel sequencing --- p.9 / Chapter 1.4.2. --- MPS-based NIPD of chromosomal aneuploidies --- p.11 / Chapter 1.4.3. --- MPS-based prenatal fetal whole-genome scanning --- p.15 / Chapter 1.5 --- Targeted massively parallel sequencing of maternal plasma --- p.19 / Chapter 1.5.1. --- Microdroplet-based PCR --- p.19 / Chapter 1.5.2. --- Molecular inversion probe --- p.20 / Chapter 1.5.3. --- On-array capture --- p.21 / Chapter 1.5.4. --- In-solution capture --- p.21 / Chapter 1.5.5. --- Implementation on plasma DNA --- p.22 / Chapter 1.6 --- Aims of this thesis --- p.29 / Chapter SECTION II : --- Feasibility of targeted MPS in maternal plasma DNA --- p.30 / Chapter CHAPTER 2: --- Targeted MPS of maternal plasma DNA permits efficient and unbiased detection of fetal alleles --- p.31 / Chapter 2.1 --- Introduction --- p.31 / Chapter 2.2 --- Methods --- p.34 / Chapter 2.2.1 --- Study participants and sample collection --- p.34 / Chapter 2.2.2 --- Sample processing and DNA extraction --- p.34 / Chapter 2.2.3 --- DNA quantification --- p.36 / Chapter 2.2.4 --- Microarray genotyping --- p.39 / Chapter 2.2.5 --- Plasma DNA library preparation --- p.39 / Chapter 2.2.6 --- Plasma DNA library validation --- p.40 / Chapter 2.2.7 --- Target enrichment --- p.44 / Chapter 2.2.8 --- Massively parallel sequencing and alignment --- p.45 / Chapter 2.3 --- Results --- p.48 / Chapter 2.3.1 --- Efficiency of target enrichment --- p.48 / Chapter 2.3.2 --- Sequence coverage within the targeted region --- p.53 / Chapter 2.3.3 --- Fetus-specific allele detection --- p.59 / Chapter 2.3.4 --- Fractional fetal DNA concentrations before and after enrichment --- p.63 / Chapter 2.4 --- Discussion --- p.66 / Chapter SECTION III : --- NIPD of trisomy 21 by targeted MPS of maternal plasma DNA --- p.71 / Chapter CHAPTER 3: --- NIPD of fetal trisomy 21 by allelic ratio analysis using targeted MPS of maternal plasma DNA --- p.72 / Chapter 3.1 --- Introduction --- p.72 / Chapter 3.2 --- Methods --- p.74 / Chapter 3.2.1 --- Study participants and sample collection --- p.74 / Chapter 3.2.2 --- Sample processing and DNA extraction --- p.74 / Chapter 3.2.3 --- Targeted MPS of plasma DNA libraries --- p.74 / Chapter 3.2.4 --- F-S ratio calculation --- p.76 / Chapter 3.2.5 --- Microarray genotyping --- p.78 / Chapter 3.2.6 --- Computer simulation --- p.78 / Chapter 3.3 --- Results --- p.80 / Chapter 3.3.1 --- Efficiency of target enrichment --- p.80 / Chapter 3.3.2 --- Estimation of fractional fetal DNA concentrations --- p.83 / Chapter 3.3.3 --- F-S ratio calculation using non-targeted sequencing data --- p.83 / Chapter 3.3.4 --- F-S ratio calculation using targeted sequencing data --- p.85 / Chapter 3.3.5 --- Computer simulation --- p.85 / Chapter 3.4 --- Discussion --- p.90 / Chapter SECTION IV : --- NIPD of monogenic diseases by targeted MPS of maternal plasma DNA --- p.94 / Chapter CHAPTER 4: --- NIPD of monogenic diseases by targeted MPS of maternal plasma: application to Beta-thalassemia --- p.95 / Chapter 4.1 --- Introduction --- p.95 / Chapter 4.2 --- Methods --- p.98 / Chapter 4.2.1 --- Sample collection and DNA extraction --- p.98 / Chapter 4.2.2 --- Microarray-based genotyping --- p.100 / Chapter 4.2.3 --- Targeted MPS of plasma DNA libraries --- p.100 / Chapter 4.2.4 --- Genotyping by Sanger sequencing --- p.103 / Chapter 4.2.5 --- Haplotyping by digital PCR --- p.105 / Chapter 4.2.6 --- RHDO analysis --- p.105 / Chapter 4.3 --- Results --- p.110 / Chapter 4.3.1 --- Effectiveness of targeted sequencing --- p.110 / Chapter 4.3.2 --- Determination of fetal HBB genotype in the first family --- p.112 / Chapter 4.3.3 --- Determination of fetal HBB genotype in the second family --- p.113 / Chapter 4.4 --- Discussion --- p.115 / Chapter SECTION V : --- CONCLUDING REMARKS --- p.120 / Chapter CHAPTER 5: --- Conclusion and future perspectives --- p.121 / Chapter 5.1 --- Targeted MPS in plasma DNA --- p.121 / Chapter 5.2 --- Targeted MPS in NIPD of chromosomal aneuploidies --- p.124 / Chapter 5.3 --- Targeted MPS in NIPD of monogenic diseases --- p.126 / Chapter Appendix I: --- Primer names and sequences for genotyping and haplotyping of βeta-globin gene cluster region --- p.128 / Chapter Appendix II: --- Primers used in PCRs and sequencing for the parents in the first family --- p.132 / Chapter Appendix III: --- Primers used in PCRs and sequencing for the parents in the second family --- p.138 / Chapter Appendix IV: --- RHDO analysis on maternal plasma DNA in the first family --- p.140 / Chapter Appendix V: --- RHDO analysis on maternal plasma DNA in the second family --- p.145 / References --- p.147

Lo, Yin Wai Wyatt. / "December 2010." / Thesis (M.D.)--Chinese University of Hong Kong, 2011. / Includes bibliographical references (leaves 186-206). / Abstracts in English and Chinese. / ABSTRACT --- p.II / 摘要 --- p.VII / ACKNOWLEDGEMENTS --- p.X / PUBLICATIONS --- p.XI / TABLE OF CONTENTS --- p.XII / LIST OF TABLES --- p.XVIII / LIST OF FIGURES --- p.XXI / LIST OF ABBREVIATIONS --- p.XXIV / Chapter SECTION I: --- BACKGROUND --- p.1 / Chapter CHAPTER 1: --- PRENATALTESTNG --- p.2 / Chapter 1.1. --- THE AIM --- p.2 / Chapter 1.2. --- INVASIVE PRENATAL DIAGNOSIS --- p.4 / Chapter 1.3. --- NONINVASIVE PRENATAL SCREENING --- p.6 / Chapter CHAPTER 2: --- NONINVASIVE PRENATAL DIAGNOSIS --- p.10 / Chapter 2.1. --- CIRCULATING FETAL CELLS IN PRENATAL DIAGNOSIS --- p.10 / Chapter 2.2. --- CIRCULATING FETAL NUCLEIC ACIDS IN PRENATAL DIAGNOSIS --- p.12 / Chapter 2.3.1. --- Biology of circulating fetal DNA . --- p.14 / Chapter 2.3.2. --- Clinical applications of circulating fetal DNA --- p.15 / Chapter 2.3.2.1. --- Qualitative analysis of fetal DNA in maternal plasma --- p.16 / Chapter 2.3.2.2. --- Quantitative analysis of fetal DNA in maternal plasma --- p.17 / Chapter 2.4. --- CIRCULATING FETAL RNA IN MATERNAL PLASMA --- p.20 / Chapter 2.4.1. --- Biology of circulating fetal RNA --- p.20 / Chapter 2.4.2. --- Clinical applications of circulating fetal RNA --- p.22 / Chapter 2.4.2.1. --- Quantitative analysis of fetal RNA in maternal plasma --- p.22 / Chapter CHAPTER 3: --- TECHNICAL CHALLENGES IN ANALYZING CIRCULATING FETAL NUCLEIC ACIDS --- p.26 / Chapter 3.1. --- INTRODUCTION --- p.26 / Chapter 3.2. --- "PREANALYTICAL ISSUES IN MATERNAL PLASMA NUCLEIC ACID ANALYSE"";" --- p.28 / Chapter 3.2.1. --- Low abundance of cell-free fetal nucleic acids in maternal plasma --- p.28 / Chapter 3.2.2. --- High level of maternal background in maternal plasma --- p.30 / Chapter 3.3. --- ANALYTICAL ISSUES IN MATERNAL PLASMA NUCLEIC ACID ANALYS --- p.IS / Chapter 3.3.1. --- Imprecise measurement of fetal nucleic acid quantity --- p.33 / Chapter 3.3.2. --- Coexistence of fetal nucleic acids and maternal nucleic acid background in maternal plasma --- p.36 / Chapter 3.4. --- AIMS OF THIS THESIS --- p.41 / Chapter SECTION II: --- MATERIALS AND METHODS --- p.42 / Chapter CHAPTER 4: --- QUANTITATIVE AND QUALITATIVE ANALYSIS OF NUCLEIC ACIDS --- p.43 / Chapter 4.1. --- SAMPLE COLLECTION AND PROCESSING --- p.43 / Chapter 4.1.1. --- Preparation of plasma and blood cells --- p.43 / Chapter 4.1.2. --- Preparation of placental tissues --- p.44 / Chapter 4.2. --- NUCLEIC ACID EXTRACTION --- p.45 / Chapter 4.2.1. --- Extraction of total RNA --- p.45 / Chapter 4.2.1.1. --- Plasma samples --- p.45 / Chapter 4.2.1.2. --- Placental tissue samples --- p.46 / Chapter 4.2.2. --- Extraction of genomic DNA --- p.48 / Chapter 4.2.2.1. --- Plasma samples --- p.48 / Chapter 4.2.2.2. --- Blood cell samples --- p.48 / Chapter 4.3. --- CONVENTIONAL REAL-TIME PCR ANALYSIS OF NUCLEIC ACIDS --- p.50 / Chapter 4.3.1. --- Principles of real-time polymerase chain reaction --- p.50 / Chapter 4.3.2. --- Quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) --- p.52 / Chapter 4.3.3. --- Quantitative polymerase chain reaction (qPCR) --- p.53 / Chapter 4.4. --- DIGITAL REAL-TIME PCR ANALYSIS OF NUCLEIC ACIDS --- p.55 / Chapter 4.4.1. --- Principles of digital PCR (dPCR) --- p.55 / Chapter 4.4.2. --- 384-reaction well dPCR v --- p.56 / Chapter 4.4.3. --- Microfluidics dPCR --- p.57 / Chapter 4.5. --- MATRIX-ASSISTED LASER DESORPTIONIONIZATION/TIME-OF-FLIGHT MASS SPECTROMETRY (MALDI-TOF MS) ANALYSIS OF NUCLEIC ACIDS --- p.59 / Chapter 4.5.1. --- Principles of MALDI-TOF MS --- p.59 / Chapter 4.5.2. --- DNA genotyping analysis by MassArray Homogenous MassExtend (hME) assay --- p.60 / Chapter 4.6. --- CLONING AND DNA SEQUENCING --- p.63 / Chapter SECTION III: --- IMPROVEMENTS ON MATERNAL PLASMA ANALYSIS OF CIRCULATING RNA --- p.65 / Chapter CHAPTER 5: --- ENRICHMENT OF PLACENTA EXPRESSED MRNA MARKERS BY WHOLE TRANSCRIPTOME PREAMPLIFICATION --- p.66 / Chapter 5.1. --- INTRODUCTION --- p.66 / Chapter 5.2. --- MATERIALS AND METHODS --- p.69 / Chapter 5.2.1. --- Study design --- p.69 / Chapter 5.2.2. --- Subjects and sample collection --- p.71 / Chapter 5.2.3. --- RNA extraction and sample dilution --- p.71 / Chapter 5.2.4. --- Preamplification --- p.73 / Chapter 5.2.5. --- qPCR analysis --- p.74 / Chapter 5.3. --- RESULTS --- p.83 / Chapter 5.3.1. --- Comparison of mRNA expression profiles in placental tissues with and without preamplification --- p.83 / Chapter 5.3.1.1. --- Undiluted placental tissue RNA --- p.84 / Chapter 5.3.1.2. --- Diluted placental tissue RNA --- p.88 / Chapter 5.3.2. --- The effect of RNA input on the degree of amplification --- p.92 / Chapter 5.3.2.1. --- Correlation between RNA input and RNA output --- p.94 / Chapter 5.3.2.2. --- Correlation between RNA input and output/input ratio --- p.96 / Chapter 5.3.3. --- Preamplification of maternal plasma RNA --- p.98 / Chapter 5.3.3.1. --- Concentrations of placenta expressed mRNA in third trimester maternal plasma --- p.98 / Chapter 5.3.3.2. --- Concentrations of placenta expressed mRNA in first trimester maternal plasma --- p.100 / Chapter 5.4. --- DISCUSSION --- p.102 / Chapter SECTION IV: --- IMPROVEMENTS ON MATERNAL PLASMA ANALYSIS OF CIRCULATING DNA --- p.105 / Chapter CHAPTER 6: --- ACCURATE GENE DOSAGE ANALYSIS BY MULTIPLEX QPCR --- p.106 / Chapter 6.1. --- INTRODUCTION --- p.106 / Chapter 6.2. --- MATERIALS AND METHODS --- p.110 / Chapter 6.2.1. --- Study design --- p.110 / Chapter 6.2.2. --- Subjects and sample collection --- p.112 / Chapter 6.2.3. --- DNA extraction and sample dilution --- p.113 / Chapter 6.2.4. --- qPCR analysis --- p.113 / Chapter 6.2.4.1. --- Monoplex assays --- p.114 / Chapter 6.2.4.2. --- Multiplex assays --- p.114 / Chapter 6.2.5. --- Microfluidics dPCR assay --- p.122 / Chapter 6.2.6. --- Gene Dosage Comparison --- p.122 / Chapter 6.2.6.1. --- In adult male samples --- p.123 / Chapter 6.2.6.2. --- In maternal plasma samples --- p.123 / Chapter 6.3. --- RESULTS --- p.125 / Chapter 6.3.1. --- The influence of using the same and different sets of primers for amplifying different chromosomal loci --- p.125 / Chapter 6.3.2. --- Effects of using monoplex and multiplex real-time PCR formulations --- p.130 / Chapter 6.3.3. --- Effects of incorporating calibration curves for template quantification in conventional qPCR --- p.135 / Chapter 6.4. --- DISCUSSION --- p.140 / Chapter CHAPTER 7: --- DPCR DETECTION OF PATERNALLY INHERITED POINT MUTATIONS --- p.144 / Chapter 7.1. --- INTRODUCTION --- p.144 / Chapter 7.2. --- MATERIALS AND METHODS --- p.153 / Chapter 7.2.1. --- Study design --- p.153 / Chapter 7.2.2. --- Subjects and sample collection --- p.157 / Chapter 7.2.3. --- DNA extraction and sample preparation --- p.158 / Chapter 7.2.4. --- MassArray hME assays --- p.159 / Chapter 7.2.5. --- dPCR assay --- p.159 / Chapter 7.3. --- RESULTS --- p.161 / Chapter 7.3.1. --- Validation of the digital HbE assay --- p.161 / Chapter 7.3.2. --- Determination of the minimum fetal DNA amount required for digital PCR detection --- p.165 / Chapter 7.3.3. --- Detection of paternally inherited fetal HbE mutation in maternal plasma --- p.172 / Chapter 7.4. --- DISCUSSION --- p.175 / Chapter SECTION V: --- CONCLUDING REMARKS --- p.180 / Chapter CHAPTER 8: --- CONCLUSION AND FUTURE PERSPECTIVES --- p.181 / Chapter 8.1. --- IMPROVEMENTS ON QUANTITATIVE AND QUALITATIVE ANALYSIS OF FETAL NUCLEIC ACIDS IN MATERNAL PLASMA --- p.181 / Chapter 8.2. --- PERSPECTIVES FOR FUTURE WORK --- p.184 / REFERENCES --- p.186

INTRODUÇÃO: A determinação do genótipo RHD fetal no plasma materno é um teste de diagnóstico pré-natal não invasivo oferecido a gestantes RhD negativo que apresentam potencial de sensibilização e/ou Doença Hemolítica Perinatal. Atualmente, este exame é realizado de rotina em diversos países, mas não no Brasil. A Clínica Obstétrica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP) oferece atendimento terciário a gestantes RhD negativo, com monitorização dos títulos de anticorpos irregulares, administração da imunoglobulina anti-D e/ou terapêutica fetal, quando necessários. OBJETIVO: Avaliar a acurácia do teste semiautomatizado para determinação do genótipo RHD fetal no plasma materno. METODOLOGIA: Foram coletadas prospectivamente amostras de sangue de 220 gestantes RhD negativo, com idade gestacional entre 8-28 semanas. O plasma foi obtido em no máximo 2 horas após a coleta, e uma alíquota de 1 mL foi submetida à extração de ácidos nucléicos no equipamento automatizado MagNA Pure Compact (Roche), empregando o kit Large Volume. O DNA extraído foi submetido a PCR em tempo real (Step One Plus - Applied Biosystems), usando o protocolo do grupo SAFE, que tem como alvos os éxons 5 e 7 do gene RHD. RESULTADOS: Ocorreu exclusão de 35 amostras devido a problemas pré-analíticos, aborto ou desconhecimento do fenótipo do recém-nascido. Entre as 185 amostras analisadas, 130 (70,2%) foram genotipadas como RHD+ e 55 (29,8%) RHD-. Os resultados obtidos foram comparados com a fenotipagem do cordão umbilical, e houve concordância completa (100%). Sete amostras exibiram amplificação exclusiva para o éxon 7. Essas amostras foram submetidas aos protocolos em PCR convencional, e PCR em tempo real específico para o pseudogene RHD. Ambos os ensaios apresentaram os mesmos resultados: cinco positivos e dois negativos. Nesses mesmos 7 casos, após extração da camada de leucócitos materna, os protocolos foram repetidos, e o resultado confirmou que cinco mães eram RHD. As duas amostras com resultado negativo foram submetidas ao protocolo Multiplex, envolvendo os éxons 3-9 do gene RHD, com resultados negativos, confirmando que as mães são verdadeiramente RHD- portanto o sinal do éxon 7 é provindo dos fetos que são D variantes. CONCLUSÃO: O método para a determinação do RHD fetal no plasma materno descrito demonstrou ser rápido, de fácil execução, alta precisão e reprodutível, além de indicar possíveis variantes RHD em nossa população / BACKGROUND: Fetal RHD genotype determination in maternal plasma is a noninvasive prenatal diagnostic test performed in RhD negative pregnant women at risk of alloimmunization and/or Hemolytic Disease of Fetus and Newborn. Currently, this test is routinely performed in many countries but not in Brazil. The Department of Obstetrics at Hospital das Clínicas, São Paulo University Medical School provides tertiary antenatal care for RhD negative pregnant women including anti-D immunoglobulin administration, antibody levels monitoring and intrauterine treatment if necessary. AIMS: To validate the accuracy of a semi-automated test for fetal RHD genotype determination in maternal plasma. METHODS: Two-hundred and twenty blood samples were prospectively collected between 8 and 28 weeks of gestational age. Plasma processing was performed within 2 hours after blood collection, and nucleic acids were extracted from 1mL aliquots with an automated extraction platform (MagNA Pure Compact Roche) and the Large Volume kit. RHD gene exons 5 and 7 were amplified with real-time PCR (Step One Plus - Applied Biosystems) using the SAFE group protocol. RESULTS: Thirty-five samples were excluded due to pre-analytical problems, miscarriage and missing follow-up. In the remaining 185 samples, 130 (70.2%) were genotyped as RhD+ and 55 (29.8%) RhD-. Comparison with umbilical cord blood group phenotype showed 100% concordance. Seven samples showed amplification for exon 7 only. These were further investigated with conventional and real-time PCR with an specific protocol for RHD? pseudogene: 5 were positive and 2, negative. In these 7 cases, maternal buffy-coat DNA analysis also confirmed that 5 women were RHD?. In the remaining 2 cases, a multiplex protocol directed at RHD gene exons 3-9 confirmed that both mothers were truly RhD negative so exon 7 signal comes from the fetuses, further found to harbor D variants. CONCLUSION: The present study demonstrates that fetal RHD determination in maternal plasma is a fast, easy-to-perform and reproducible technique with high accuracy in our population. Moreover, it helps in the identification of possible RHD variants in our population

INTRODUÇÃO: A determinação do genótipo RHD fetal no plasma materno é um teste de diagnóstico pré-natal não invasivo oferecido a gestantes RhD negativo que apresentam potencial de sensibilização e/ou Doença Hemolítica Perinatal. Atualmente, este exame é realizado de rotina em diversos países, mas não no Brasil. A Clínica Obstétrica do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo (HCFMUSP) oferece atendimento terciário a gestantes RhD negativo, com monitorização dos títulos de anticorpos irregulares, administração da imunoglobulina anti-D e/ou terapêutica fetal, quando necessários. OBJETIVO: Avaliar a acurácia do teste semiautomatizado para determinação do genótipo RHD fetal no plasma materno. METODOLOGIA: Foram coletadas prospectivamente amostras de sangue de 220 gestantes RhD negativo, com idade gestacional entre 8-28 semanas. O plasma foi obtido em no máximo 2 horas após a coleta, e uma alíquota de 1 mL foi submetida à extração de ácidos nucléicos no equipamento automatizado MagNA Pure Compact (Roche), empregando o kit Large Volume. O DNA extraído foi submetido a PCR em tempo real (Step One Plus - Applied Biosystems), usando o protocolo do grupo SAFE, que tem como alvos os éxons 5 e 7 do gene RHD. RESULTADOS: Ocorreu exclusão de 35 amostras devido a problemas pré-analíticos, aborto ou desconhecimento do fenótipo do recém-nascido. Entre as 185 amostras analisadas, 130 (70,2%) foram genotipadas como RHD+ e 55 (29,8%) RHD-. Os resultados obtidos foram comparados com a fenotipagem do cordão umbilical, e houve concordância completa (100%). Sete amostras exibiram amplificação exclusiva para o éxon 7. Essas amostras foram submetidas aos protocolos em PCR convencional, e PCR em tempo real específico para o pseudogene RHD. Ambos os ensaios apresentaram os mesmos resultados: cinco positivos e dois negativos. Nesses mesmos 7 casos, após extração da camada de leucócitos materna, os protocolos foram repetidos, e o resultado confirmou que cinco mães eram RHD. As duas amostras com resultado negativo foram submetidas ao protocolo Multiplex, envolvendo os éxons 3-9 do gene RHD, com resultados negativos, confirmando que as mães são verdadeiramente RHD- portanto o sinal do éxon 7 é provindo dos fetos que são D variantes. CONCLUSÃO: O método para a determinação do RHD fetal no plasma materno descrito demonstrou ser rápido, de fácil execução, alta precisão e reprodutível, além de indicar possíveis variantes RHD em nossa população / BACKGROUND: Fetal RHD genotype determination in maternal plasma is a noninvasive prenatal diagnostic test performed in RhD negative pregnant women at risk of alloimmunization and/or Hemolytic Disease of Fetus and Newborn. Currently, this test is routinely performed in many countries but not in Brazil. The Department of Obstetrics at Hospital das Clínicas, São Paulo University Medical School provides tertiary antenatal care for RhD negative pregnant women including anti-D immunoglobulin administration, antibody levels monitoring and intrauterine treatment if necessary. AIMS: To validate the accuracy of a semi-automated test for fetal RHD genotype determination in maternal plasma. METHODS: Two-hundred and twenty blood samples were prospectively collected between 8 and 28 weeks of gestational age. Plasma processing was performed within 2 hours after blood collection, and nucleic acids were extracted from 1mL aliquots with an automated extraction platform (MagNA Pure Compact Roche) and the Large Volume kit. RHD gene exons 5 and 7 were amplified with real-time PCR (Step One Plus - Applied Biosystems) using the SAFE group protocol. RESULTS: Thirty-five samples were excluded due to pre-analytical problems, miscarriage and missing follow-up. In the remaining 185 samples, 130 (70.2%) were genotyped as RhD+ and 55 (29.8%) RhD-. Comparison with umbilical cord blood group phenotype showed 100% concordance. Seven samples showed amplification for exon 7 only. These were further investigated with conventional and real-time PCR with an specific protocol for RHD? pseudogene: 5 were positive and 2, negative. In these 7 cases, maternal buffy-coat DNA analysis also confirmed that 5 women were RHD?. In the remaining 2 cases, a multiplex protocol directed at RHD gene exons 3-9 confirmed that both mothers were truly RhD negative so exon 7 signal comes from the fetuses, further found to harbor D variants. CONCLUSION: The present study demonstrates that fetal RHD determination in maternal plasma is a fast, easy-to-perform and reproducible technique with high accuracy in our population. Moreover, it helps in the identification of possible RHD variants in our population