| dc.contributor.author | Harris, Andrew S. | en_US |
| dc.date.accessioned | 2014-10-21T12:36:51Z | |
| dc.date.available | 1995 | |
| dc.date.issued | 1995 | en_US |
| dc.identifier.other | AAINN05272 | en_US |
| dc.identifier.uri | http://hdl.handle.net/10222/55063 | |
| dc.description | This thesis describes the isolation and characterization of three minisatellites or variable number of tandem repeats (VNTR's) from the cichlid fish, Oreochromis niloticus. The human-derived polycore probes of Jeffreys, 33.6 and 33.15, generate multilocus DNA fingerprint patterns of hybridization in tilapia, that are consistent with Mendelian inheritance of minisatellite loci. The utility of these human polycore probes as tools for describing inheritance in tilapiines was tested by examining the economic heterozygocity of gynogenetic individuals. Analysis of hybridization patterns showed reductions in the number of fragments produced in mitotic gynogens over meiogynes and controls, consistent with expected reductions in genomic heterozygocity. | en_US |
| dc.description | A second objective of this study was the isolation and description of minisatellite loci from tilapia. A genomic DNA library of O. niloticus sequences was screened with the human-derived 33.6 and 33.15 probes. This revealed that minisatellite VNTRs related by sequence to these probes are present every 1000 kbp in the tilapia genome. Hybridization studies of cloned VNTRs from tilapia revealed many of the properties described for human minisatellites such as the grouping of minisatellite loci into families based on sequence identity and the clustering of minisatellite arrays. | en_US |
| dc.description | A third objective of this study was to describe the sequence of VNTR's in tilapia. Variability at these loci is low compared to minisatellites previously described from humans. Repeat unit length and variability of the repeated sequence differed considerably between the loci. | en_US |
| dc.description | Finally, this study examines the evolution of VNTR's from tilapiines. Each minisatellite was hybridized to genomic DNA from a number of related taxa. Detection of similar sequences in other species varied for the three cloned minisatellites. Clones OniMS17 and OniMS32 showed hybridization only to genomic DNA of species in the tilapiine tribe and the closely related African cichlid Haplochromis moori, whereas clone OniMS34 showed hybridisation to the genomic DNA of the South American cichlid Cichlasoma otofasciatus. The sequence and varient repeat structure of two of the loci suggest mechanisms of generation for these minisatellites. | en_US |
| dc.description | Thesis (Ph.D.)--Dalhousie University (Canada), 1995. | en_US |
| dc.language | eng | en_US |
| dc.publisher | Dalhousie University | en_US |
| dc.publisher | | en_US |
| dc.subject | Biology, Molecular. | en_US |
| dc.subject | Biology, Zoology. | en_US |
| dc.subject | Agriculture, Fisheries and Aquaculture. | en_US |
| dc.title | Organization and evolution of minisatellite VNTR's in the tilapiine genome. | en_US |
| dc.type | text | en_US |
| dc.contributor.degree | Ph.D. | en_US |
