Estimates of genetic parameters for growth and wood properties in Eucalyptus pellita F. Muell. to support tree breeding in Vietnam

Eucalyptus pellita demonstrated good growth and wood quality traits in this study, with young plantation grown timber being suitable for both solid and pulp wood products. All traits examined were under moderate levels of genetic control with little genotype by environment interaction when grown on two contrasting sites in Vietnam. Eucalyptus pellita currently has a significant role in reforestation in the tropics. Research to support expanded of use of this species is needed: particularly, research to better understand the genetic control of key traits will facilitate the development of genetically improved planting stock. This study aimed to provide estimates of the heritability of diameter at breast height over bark, wood basic density, Kraft pulp yield, modulus of elasticity and microfibril angle, and the genetic correlations among these traits, and understand the importance of genotype by environment interactions in Vietnam. Data for diameter and wood properties were collected from two 10-year-old, open-pollinated progeny trials of E. pellita in Vietnam that evaluated 104 families from six native range and three orchard sources. Wood properties were estimated from wood samples using near-infrared (NIR) spectroscopy. Data were analysed using mixed linear models to estimate genetic parameters (heritability, proportion of variance between seed sources and genetic correlations). Variation among the nine sources was small compared to additive variance. Narrow-sense heritability and genetic correlation estimates indicated that simultaneous improvements in most traits could be achieved from selection among and within families as the genetic correlations among traits were either favourable or close to zero. Type B genetic correlations approached one for all traits suggesting that genotype by environment interactions were of little importance. These results support a breeding strategy utilizing a single breeding population advanced by selecting the best individuals across all seed sources. Both growth and wood properties have been evaluated. Multi-trait selection for growth and wood property traits will lead to more productive populations of E. pellita both with improved productivity and improved timber and pulp properties.

Genetic variation in growth and wood-quality traits of Corymbia citriodora subsp. variegata across three sites in south-east Queensland, Australia

Ten growth or wood-quality traits were assessed in three nearby Corymbia citriodora subsp. variegata (CCV) open-pollinated family-within-provenance trials (18 provenances represented by a total of 374 families) to provide information for the development of a breeding program targeting both pulp and solid-wood products. Growth traits (diameter at breast high over bark [DBH], height and conical volume) were assessed at 3 and 7 years of age. Wood-quality traits (density [DEN], Kraft pulp yield [KPY], modulus of elasticity [MoE] and microfibril angle [MfA]) were predicted using near-infrared spectroscopy on wood samples collected from these trials when aged between 10 and 12 years. The high average KPY, DEN and MoE, and low average MfA observed indicates CCV is very suitable for both pulp and timber products. All traits were under moderate to strong genetic control. In across- trials analyses, high (>0.4) heritability estimates were observed for height, DEN, MoE and MfA, while moderate heritability estimates (0.24 to 0.34) were observed for DBH, volume and KPY. Most traits showed very low levels of genotype × site interaction. Estimated age–age genetic correlations for growth traits were strong at both the family (0.97) and provenance (0.99) levels. Relationships among traits (additive genetic correlation estimates) were favourable, with strong and positive estimates between growth traits (0.84 to 0.98), moderate and positive values between growth and wood-quality traits (0.32 to 0.68), moderate and positive between KPY and MoE (0.64), and high and positive between DEN and MoE (0.82). However, negative (but favourable) correlations were detected between MfA and all other evaluated traits (−0.31 to −0.96). The genetic correlation between the same trait expressed on two different sites, at family level, ranged from 0.24 to 0.42 for growth traits, and from 0.29 to 0.53 for wood traits. Therefore simultaneous genetic improvement of growth and wood property traits in CCV for the target environment in south-east Queensland should be possible, given the moderate to high estimates of heritability and favourable correlations amongst all traits studied, unless genotype × site interactions are greater than was evident. © 2016 NISC (Pty) Ltd

Genetic architecture and sexual conflict in the life history of Drosophila

Because males and females of a species express many homologous traits, sex-specific selection on these traits can shift the opposite sex away from its phenotypic optimum. This mode of sexually antagonistic selection, known as intralocus sexual conflict (IaSC), arises when the evolution of sexual dimorphism is constrained by the two sexes sharing a common gene pool. As IaSC has been historically overlooked, many outstanding questions remain. For example, what is its contribution in maintaining genetic variation for fitness in populations? What characters underlie this variation in fitness? How does the selection history of the population influence the standing genetic variation? I used the model organism Drosophila melanogaster to attempt to resolve some of these questions. The first part of my Master’s project involved assessing the detectability of sexually antagonistic alleles in populations at different stages of adaptation to the laboratory. For the second part of my Master’s project, I looked for evidence of conflict during the development of body size, a well-known sexually dimorphic trait. While the first part of my thesis proved inconclusive, the second part revealed a surprising source of sexual conflict in pre-adult stages of D. melanogaster.

Genetic Polymorphisms in Replication-related Genes and Risk of Breast Cancer Among European and East Asian Women

Background: The role of common, low to intermediate risk alleles in breast cancer need to be examined due to their relatively high prevalence. Among many cellular pathways, replication has a pivotal role in cell division and frequently targeted during carcinogenesis. Replication is governed by a host of genes involved in a number of different pathways. This study investigates the effects of replication-gene variants in relation to breast cancer and how this relationship is affected by ethnicity, menopausal status and breast tumour subtype. Methods: Data from a case-control study with 997 incident breast cancer cases and 1,050 age frequency matched controls in Vancouver, British Columbia and Kingston, Ontario were used. Unconditional logistic regression was used to calculate odds ratios between 45 replication gene variants and breast cancer risk, assuming an additive genetic model adjusted for age and centre, presented for Europeans and East Asians separately. Polytomous logistic regression was used to assess odds ratios between each SNP and four breast cancer subtypes defined by hormone receptor status among Europeans. All analyses were stratified by menopausal status. The Benjamini–Hochberg false discovery rate (FDR) was used to address multiple comparisons. Results: Among Europeans, the SNPs in FGFR2, TOX3 and 11q13 loci were associated with breast cancer after controlling for multiple comparisons. Test of heterogeneity showed the SNPs rs1045185, rs4973768, rs672888, rs1219648, rs2420946 among Europeans and rs889312 among East Asians conferred differential risk across the tumour subtypes. Conclusions: Specific SNPs in replication genes were associated with breast cancer, and the risk level differed by tumour subtype defined by ER/PR/Her2 status and ethnicity.

WIPO and the Reinforcement of the Nagoya Protocol: Towards Effective Implementation of an Access and Benefit Sharing Regime for the Protection of Traditional Knowledge Associated with Genetic Resources

Traditional knowledge associated with genetic resources (TKaGRs) is acknowledged as a valuable resource. Its value draws from economic, social, cultural, and innovative uses. This value places TK at the heart of competing interests as between indigenous peoples who hold it and depend on it for their survival, and profitable industries which seek to exploit it in the global market space. The latter group seek, inter alia, to advance and maintain their global competitiveness by exploiting TKaGRs leads in their research and development activities connected with modern innovation. Biopiracy remains an issue of central concern to the developing world and has emerged in this context as a label for the inequity arising from the misappropriation of TKaGRs located in the South by commercial interests usually located in the North. Significant attention and resources are being channeled at global efforts to design and implement effective protection mechanisms for TKaGRs against the incidence of biopiracy. The emergence and recent entry into force of the Nagoya Protocol offers the latest example of a concluded multilateral effort in this regard. The Nagoya Protocol, adopted on the platform of the Convention on Biological Diversity (CBD), establishes an open-ended international access and benefit sharing (ABS) regime which is comprised of the Protocol as well as several complementary instruments. By focusing on the trans-regime nature of biopiracy, this thesis argues that the intellectual property (IP) system forms a central part of the problem of biopiracy, and so too to the very efforts to implement solutions, including through the Nagoya Protocol. The ongoing related work within the World Intellectual Property Organization (WIPO), aimed at developing an international instrument (or a series of instruments) to address the effective protection of TK, constitutes an essential complementary process to the Nagoya Protocol, and, as such, forms a fundamental element within the Nagoya Protocol’s evolving ABS regime-complex. By adopting a third world approach to international law, this thesis draws central significance from its reconceptualization of biopiracy as a trans-regime concept. By construing the instrument(s) being negotiated within WIPO as forming a central component part of the Nagoya Protocol, this dissertation’s analysis highlights the importance of third world efforts to secure an IP-based reinforcement to the Protocol for the effective eradication of biopiracy.