Abstract . A draft of the whole human genomic sequence has been completed and published in 2001. Researches on structural genomics, functional genomics, proteomics, evolutionary and medical sciences have just begun since. The existence of ninety percent repetitive, non-coding sequences in the human genome and in other mammalian species as well, indicating some potential but unaware functions of these repetitive regions within the mammalian genomes remained to be discovered. Among all features in the genomic sequences, microsatellite has been characterized as one type of short tandem repeats (STRs), abundant in the human genome, which potentially plays some important roles in biological processes, such as makers for molecular biology, the enhancers for transcription, and protein-binding sites. Changes on microsatellite copy numbers also involve in the cause of a couple of diseases have been reported. The sequence of human chromosome 20 has been finished in Dec. 2001, which provided us a valuable resource to study about gene density and the distribution of repetitive sequences such as microsatellties as well. To build a more detail chromosome 20 microsatellite map, including di-, tri- and tetra-nucleotide microsatellites, we therefore designed a sequence-based, molecular markers discovery system by bioinformatics approaches. The results indicate that these repetitive sequences distribute across the chromosome 20 evenly. We further analyzed the GC content of the human chromosome 20. A comparison of GC content, microsatellite distribution and gene density of each contig shows some correlation among them. The slippage rates of di-nucleotide microsatellite were predicted by the formula basing on Markov Chain. Some interesting results were found in this thesis. The same approaches were applied on human chromosome 14, which was being completed sequencing in Feb. 2003. The results implied that our strategies might be useful in the advanced genetic studied or medicine researches.

No description available.

Thesis (Ph. D.)--University of Queensland, 2003. / Includes bibliographical references.

The purpose of this research was to examine four selected human population groups, institutionalized and normal, to determine the prevalence of the 47, XYY chromosome abnormality among adult males.

Copies of author's previously published articles inserted. / Bibliography : leaves 194-222. / vii, 231 leaves, [50] leaves of plates : ill. (chiefly col.) ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Cytogenetics and Molecular Genetics, 1998

Thesis (Ph. D.)--University of Washington, 1997. / Vita. Includes bibliographical references (leaves [202]-262).

Thesis (M. Ed.)--Kutztown State College. / Source: Masters Abstracts International, Volume: 45-06, page: 3060. Typescript. Includes bibliographical references (leaves 32-34).

No description available.

No description available.

DiGeorge syndrome (DGS) is a developmental defect associated with deletions in chromosomal region 22q11.2. Recently, other syndromes (Velo-Cardio-Facial syndrome, Conotruncal Anomaly Face syndrome, isolated conotruncal cardiopathy) with overlapping phenotypes have been found to be associated with deletions of a similar extent in this chromosomal region. All these syndromes have been grouped under the acronym CATCH 22 (Cardiac defect, Abnormal facies, Thymic hypoplasia, Cleft palate, Hypocalcemia, chromosome 22q11.2 deletions). In order to characterize genetically this group of syndromes, we have searched for deletions in the 22q11.2 chromosomal region by fluorescence in situ hybridization (FISH). A set of 6 cosmid probes dispersed within the whole length of the DGS deleted region was used to screen 23 patients. A 22q11.2 deletion was observed in 96% of the patients studied. Furthermore, there does not seem to exist any correlation between the size of the deletion and the phenotype observed, since the majority of patients studied, although widely divergent in their clinical manifestation of DGS, appeared to present the same extent of deletion in this genomic region. / There appears to be a predominance of deletion-bearing mothers in familial CATCH 22 when published pedigrees are examined. Furthermore, our own familial cases and the sporadic cases where the parental origin of the deletion could be deduced using a chromosome 22 short arm heteromorphisms seem to confirm this tendency. Because we had isolated a CA-repeat locus mapping within the DGS deleted region, the parental origin of the deletion in sporadic DGS/VCFS cases was studied by assessing the inheritance pattern of this microsatellite marker. The deleted portion of chromosome 22 was of maternal origin in 16 out of 22 cases (72%). When cases of sporadic, familial and unbalanced translocation inheritance reported in the literature were pooled with these results, there appears to be a net tendency for the deletions to be of maternal origin in CATCH 22 (70 deletions of maternal origin, 21 of paternal origin, X$ sp2$ = 26.4, p $<$ 0.0001). / In order to identify the molecular defect underlying DGS, we embarked on a positional cloning approach. A detailed physical map of the 22q11.2 region was made using one- and two-color FISH on metaphases and G$ sb0$ interphase nuclei, and by hybridization to a chromosome 22 hybrid panel. This permitted delineation of a critical region, within which the breakpoint of a balanced translocation carrier affected with DGS was mapping. This breakpoint was cloned by the construction of cosmid contigs, and a novel gene mapped to this region was isolated. The gene potentially encodes an adhesion receptor, and is not interrupted by the balanced translocation breakpoint. Possible mechanisms through which this gene can be involved in the pathogenesis of DGS are presented. / This research project has contributed toward the understanding of the genetics of DGS and related syndromes. Furthermore, a candidate gene for the CATCH 22 syndromes has been isolated and further work will confirm whether it plays a major role in the pathogenesis of these syndromes.