Development of molecular genetic markers in Atlantic salmon (Salmo salar) and an illustration of their application to aquaculture and fisheries.

• Main Author: O'Reilly, Patrick Terrance.
• Other Authors: Ph.D.
• Format: Text
• Language: English
• Published: Dalhousie University 2014
• Subjects: Biology; Molecular; Genetics; Agriculture; Fisheries and Aquaculture; Canada; Atlantic salmon; Salmo salar
• Online Access: http://hdl.handle.net/10222/55497

DNA fingerprinting technology has changed considerably over the last decade. With the advent of PCR-based methods, new avenues of inquiry-are becoming accessible. However, our understanding of the processes responsible for creating variation at mini- and microsatellite loci is poorly understood. Also, little effort has been made to evaluate the accuracy of these technologies, or the implications of mutations or scoring errors on the interpretation of results. Here, I have characterized several minisatellite loci from Atlantic salmon (Salmo salar), and have developed MVR-PCR technology at one. I have also isolated and sequenced over 180 microsatellites from this species, and have developed a primarily tetranucleotide microsatellite-based multiplex system for efficient and accurate analysis of genetic variation. Due to the high variability of these loci ($>$87% heterozygosity at all three tetranucleotide loci), fewer than two in 30,000 individuals are expected to exhibit identical composite genotypes. To evaluate the utility of this system for assessment of population differentiation, genetic variation was surveyed in 3 rivers from Nova Scotia, Canada. Significant differences in allele frequencies were observed between all Atlantic salmon populations surveyed. In the second segment of this research, approximately 800 communally reared offspring, and their 12 possible sets of parents, were typed at four multiplex loci. The goals of this research were: (1) to analyze the resolution and accuracy of the multiplex system in determining parentage, and (2) to assess rates of mutation at these loci. Over 99.6% of offspring could be unambiguously matched to one set of parents in the original 12 x 1 cross (each of 12 males uniquely crossed to one of 12 females) and in the simulated 36 x 1 cross; and over 80% in a 12 x 12 cross (involving multiple half-sib matings). Of the approximately 6,400 parent-offspring transfers of alleles screened in this parentage study, only two mutations were observed. The overall combined mutation at these four loci was estimated to be 3.4 x 10-4 per gamete. Thesis (Ph.D.)--Dalhousie University (Canada), 1997.