Optimal cross selection for long-term genetic gain in two-part programs with rapid recurrent genomic selection

This study evaluates optimal cross selection to balance selection and maintenance of genetic diversity in two-part plant breeding programs with rapid recurrent genomic selection. The two-part program reorganizes a conventional breeding program into a population improvement component with recurrent genomic selection to increase the mean value of germplasm and a product development component with standard methods to develop new lines. Rapid recurrent genomic selection has a large potential, but is challenging due to genotyping costs or genetic drift. Here we simulate a wheat breeding program for 20 years and compare optimal cross selection against truncation selection in the population improvement component with one to six cycles per year. With truncation selection we crossed a small or a large number of parents. With optimal cross selection we jointly optimised selection, maintenance of genetic diversity, and cross allocation with AlphaMate program. The results show that the two-part program with optimal cross selection delivered the largest genetic gain that increased with the increasing number of cycles. With four cycles per year optimal cross selection had 78% (15%) higher long-term genetic gain than truncation selection with a small (large) number of parents. Higher genetic gain was achieved through higher efficiency of converting genetic diversity into genetic gain; optimal cross selection quadrupled (doubled) efficiency of truncation selection with a small (large) number of parents. Optimal cross selection also reduced the drop of genomic selection accuracy due to the drift between training and prediction populations. In conclusion, optimal cross-selection enables optimal management and exploitation of population improvement germplasm in two-part programs

Reducing disease burden and health inequalities arising from chronic disease among indigenous children: an early childhood caries intervention in Aotearoa/New Zealand

BACKGROUND Maaori are the Indigenous people of New Zealand and do not enjoy the same oral health status as the non-Indigenous majority. To overcome oral health disparities, the life course approach affords a valid foundation on which to develop a process that will contribute to the protection of the oral health of young infants. The key to this process is the support that could be provided to the parents or care givers of Maaori infants during the pregnancy of the mother and the early years of the child. This study seeks to determine whether implementing a kaupapa Maaori (Maaori philosophical viewpoint) in an early childhood caries (ECC) intervention reduces dental disease burden among Maaori children. The intervention consists of four approaches to prevent early childhood caries: dental care provided during pregnancy, fluoride varnish application to the teeth of children, motivational interviewing, and anticipatory guidance. METHODS/DESIGN The participants are Maaori women who are expecting a child and who reside within the Maaori tribal area of Waikato-Tainui. This randomised-control trial will be undertaken utilising the principles of kaupapa Maaori research, which encompasses Maaori leadership, Maaori relationships, Maaori customary practices, etiquette and protocol. Participants will be monitored through clinical and self-reported information collected throughout the ECC intervention. Self-report information will be collected in a baseline questionnaire during pregnancy and when children are aged 24 and 36 months. Clinical oral health data will be collected during standardised examinations at ages 24 and 36 months by calibrated dental professionals. All participants receive the ECC intervention benefits, with the intervention delayed by 24 months for participants who are randomised to the control-delayed arm. Discussion The development and evaluation of oral health interventions may produce evidence that supports the application of the principles of kaupapa Maaori research in the research processes. This study will assess an ECC intervention which could provide a meaningful approach for Maaori for the protection and maintenance of oral health for Maaori children and their family, thus reducing oral health disparities. TRIAL REGISTRATION Australia and New Zealand Clinical Trials Register (ANZCTR): ACTRN12611000111976.John R Broughton, Joyce Te H Maipi, Marie Person, W Murray Thomson, Kate C Morgaine, Sarah-Jane Tiakiwai, Jonathan Kilgour, Kay Berryman, Herenia P Lawrence, Lisa M Jamieso

'I felt weird and wobbly.' Child-reported impacts associated with a dental general anaesthetic

Aim This qualitative study sought to obtain children's accounts of having dental extractions under general anaesthesia (GA). The aim was to gain greater understanding of the physical and psychological impacts from a child's perspective. Method Ten children, aged 6-11 years, maintained a video diary to document their feelings and experiences before, and following their hospital admission. Two semi-structured home interviews supplemented the video diary data and analysis was guided by narrative approaches. Results This research revealed new insights into children's experiences of having teeth removed under GA. Several of the post-operative impacts correlated with those previously reported by parents/carers. These were notably nausea, bleeding and tiredness, although children used different terminology. However, additional physical and psychological outcomes, both positive and negative, emerged from the children's narratives. Negative aspects included hunger, disturbed eating, being scared/worried and experiencing discomfort from the IV cannula. Interestingly, pain was not a strong theme. Positive outcomes were also reported, such as satisfaction with the resolution of their dental problem and receipt of rewards and attention from family members. Conclusion These accounts have implications for improving patient experiences and outcomes throughout the dental GA care pathway. A review of pre-operative fasting protocols should be a priority