No description available.

No description available.

The pattern of inactivation in the DXS8237E-UBE1-PCTK1 region is of particular interest, since the mechanisms of X chromosome inactivation and the escape from inactivation are, as yet, not fully understood. The inactivation status of the DXS8237E and PCTKl gene differ: the first undergoes normal inactivation and the second escapes this process. The status of the UBEl gene has been controversial, although it is widely excepted that it does escape X chromosome inactivation. Physical mapping of the region employing YACs and subsequently P ACs has been undertaken, but was restricted in scope by the high frequency of rearrangements occurring. DNA sequences between DXS8237E, UBE1, PCTKl and the distal gene, UHX1, have been investigated with regard to LINEI elements, which are thought to playa role in X-inactivation. The results obtained strongly suggest a link between LINE1 elements and X chromosome inactivation. Sequence analysis results also contributed to the understanding of difficulties with restriction mapping of the region. Further, this work includes the first reported establishment of the UBEl exonintron boundaries. Additionally, genomic sequence analysis showed that only 46kb separate DXS8237E from UHX1, which confirms that this region is extremely gene rich.

No description available.

Copies of author's previously published articles inserted. / Includes bibliographic references. / vii, 200, [74] leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Addresses a need for more highly informative markers to be placed on high density cytogenetic-based physical and genetic linkage maps of chromosome 16. / Thesis (Ph.D.)--University of Adelaide, Dept. of Paediatrics, Women's and Children's Hospital, 1994

The cultivated sunflower (Helianthus annuus L., x=17) is one of the most important annual oilseed crops in the world. There are very few publicly shared sequence-based DNA markers and genetic maps in sunflower, even though molecular DNA markers and genetic maps have become widely used in all areas of genetic research and breeding in plant species. The objectives of this study were to develop sequence-based molecular markers and utilize the markers for genetic analyses and constructing maps in the cultivated sunflower. A total of 131 functional simple sequence repeat (SSR) markers were developed for 16 elite inbred lines using a small insert genomic library enriched for short simple sequence repeats. The polymorphism information content (PIC) estimated from 74 polymorphic SSR markers ranged from 0.0 to 0.93 with mean value of 0.55. Tetranucleotide repeats were significantly more polymorphic than dinucleotide and trinucleotide repeats, and no obvious correlation was found between repeat numbers and PIC scores. Genetic distance among 16 inbred lines, estimated from 74 polymorphic SSR markers ranged 0.175 to 0.543. Principal coordinate and cluster analyses of the genetic distance matrix well explained the difference between oilseed lines and confectionery lines, and sterility maintainer lines and fertility restorer lines. A total of 1,090 SSR markers were screened for polymorphism between the parents of two mapping populations. The two genetic maps were constructed by genotyping 94 recombinant inbred lines from a cross between PHA and PHB (276 SSR loci covering 1377.4 cM with mean distance of 4.99 cM), and 94 F��� progeny from a cross between HA370 and HA372 (122 SSR loci integrated into the existing RFLP framework map covering 1348.0 cM with mean distance of 6.77 cM). Ninety-three percent of the SSR markers were mapped to single loci and 56.5% of the loci were co-dominant. Clustering of SSR loci was observed near centromeric regions and most of the distorted loci were mapped to centromeric or distal regions. A concerted effort to develop SSR markers and generate highresolution SSR maps will enhance future fingerprinting analyses, fine-scale genome analyses and molecular breeding in the cultivated sunflower. / Graduation date: 2002

The data used for the construction of genome maps is imperfect, therefore the mapping of a physically linear structure must take place in a very uneven feature space. As the number of genes to be ordered grows, it appears to be impractical to use exhaustive search techniques to find the optimal mapping. In this paper we compare genetic algorithms and simulated annealing, two methods that are widely believed to be well-suited to non-smooth feature spaces, and find that the genetic algorithm approach yields superior results. Here we present performance profiles of comparable implementations of both genetic algorithms and simulated annealing. We have translated the problem to a form comparable to the shortest-path problem and found that the ability of a genetic algorithm to combine different partial solutions seems to be responsible for its superiority over the simulated annealing method. This is because in the genome mapping problem, as in the Traveling Salesman Problem, good solutions tend to be rather sparse and because optimal subtours tend to be components of nearly optimal tours. / Graduation date: 1994

Thesis (Ph.D.) -- University of Texas at Arlington, 2008.

Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves [128]-144). Also available on the Internet.

Thesis (Ph. D.)--University of Missouri-Columbia, 2003. / Typescript. Vita. Includes bibliographical references (leaves [128]-144). Also available on the Internet.