So far in this course we have dealt entirely with the evolution of characters that are controlled by simple Mendelian inheritance at a single locus. There are notes on the course website about gametic disequilibrium and how allele frequencies change at two loci simultaneously, but we didn’t discuss them. In every example we’ve considered we’ve imagined that we could understand something about evolution by examining the evolution of a single gene. That’s the domain of classical population genetics. For the next few weeks we’re going to be exploring a field that’s actually older than classical population genetics, although the approach we’ll be taking to it involves the use of population genetic machinery. If you know a little about the history of evolutionary biology, you may know that after the rediscovery of Mendel’s work in 1900 there was a heated debate between the “biometricians” (e.g., Galton and Pearson) and the “Mendelians” (e.g., de Vries, Correns, Bateson, and Morgan). Biometricians asserted that the really important variation in evolution didn’t follow Mendelian rules. Height, weight, skin color, and similar traits seemed to

Human biochemical genetics

Climate change could potentially interrupt progress toward a world without hunger. A robust and coherent global pattern is discernible of the impacts of climate change on crop productivity that could have consequences for food availability. The stability of whole food systems may be at risk under climate change because of short-term variability in supply. However, the potential impact is less clear at regional scales, but it is likely that climate variability and change will exacerbate food insecurity in areas currently vulnerable to hunger and undernutrition. Likewise, it can be anticipated that food access and utilization will be affected indirectly via collateral effects on household and individual incomes, and food utilization could be impaired by loss of access to drinking water and damage to health. The evidence supports the need for considerable investment in adaptation and mitigation actions toward a “climate-smart food system” that is more resilient to climate change influences on food security.

Climate change impacts on global food security

https://faculty.mtsac.edu/cbriggs/Improvement%20of%20Maternal%20and%20Child%20Nutrition%202013.pdf

Evidence-based interventions for improvement of maternal and child nutrition: What can be done and at what cost?

has grown since The Lancet Series on Maternal and Child Undernutrition in 2008. We did a comprehensive update of interventions to address undernutrition and micronutrient defi ciencies in women and children and used standard methods to assess emerging new evidence for delivery platforms. We modelled the eff ect on lives saved and cost of these interventions in the 34 countries that have 90% of the world’s children with stunted growth. We also examined the eff ect of various delivery platforms and delivery options using community health workers to engage poor populations and promote behaviour change, access and uptake of interventions. Our analysis suggests the current total of deaths in children younger than 5 years can be reduced by 15% if populations can access ten evidence-based nutrition interventions at 90% coverage. Accelerated gains are possible and about a fi fth of the existing burden of stunting can be averted using these approaches, if access is improved in this way. The estimated total additional annual cost involved for scaling up access to these ten direct nutrition interventions in the 34 focus countries is Int$9·6 billion per year. Continued investments in nutrition-specifi c interventions to avert maternal and child undernutrition and micronutrient defi ciencies through community engagement and delivery strategies that can reach poor segments of the population at greatest risk can make a great diff erence. If this improved access is linked to nutrition-sensitive approaches—ie, women’s empowerment, agriculture, food systems, education, employment, social protection, and safety nets—they can greatly accelerate progress in countries with the highest burden of maternal and child undernutrition and mortality.

https://www.thelancet.com/pdfs/journals/lancet/PIIS0140673613609964.pdf

Maternal and Child Nutrition 2 Evidence-based interventions for improvement of maternal and child nutrition: what can be done and at what cost?

To feed the several billion people living on this planet, the production of high-quality food must increase with reduced inputs, but this accomplishment will be particularly challenging in the face of global environmental change. Plant breeders need to focus on traits with the greatest potential to increase yield. Hence, new technologies must be developed to accelerate breeding through improving genotyping and phenotyping methods and by increasing the available genetic diversity in breeding germplasm. The most gain will come from delivering these technologies in developing countries, but the technologies will have to be economically accessible and readily disseminated. Crop improvement through breeding brings immense value relative to investment and offers an effective approach to improving food security.

https://science.sciencemag.org/content/sci/327/5967/818.full.pdf

Breeding Technologies to Increase Crop Production in a Changing World

Micronutrient malnutrition affects over 2 billion people in the developing world. Iron (Fe) deficiency alone affects >47% of all preschool aged children globally, often leading to impaired physical growth, mental development, and learning capacity. Zinc (Zn) deficiency, like iron, is thought to affect billions of people, hampering growth and development, and destroying immune systems. In many micronutrient-deficient regions, wheat is the dominant staple food making up >50% of the diet. Biofortification, or harnessing the powers of plant breeding to improve the nutritional quality of foods, is a new approach being used to improve the nutrient content of a variety of staple crops. Durum wheat in particular has been quite responsive to breeding for nutritional quality by making full use of the genetic diversity of Fe and Zn concentrations in wild and synthetic parents. Micronutrient concentration and genetic diversity has been well explored under the HarvestPlus biofortification research program, an...

/pdf/biofortification-of-durum-wheat-with-zinc-and-iron-2jpdb1usen.pdf

Biofortification of durum wheat with zinc and iron

BackgroundThe density of minerals and vitamins in food staples eaten widely by the poor may be increased either through conventional plant breeding or through the use of transgenic techniques, a pr...

https://journals.sagepub.com/doi/pdf/10.1177/15648265110321S105

Biofortification: A New Tool to Reduce Micronutrient Malnutrition

Deficiencies of vitamin A, iron, and zinc affect over one-half of the world's population. Progress has been made to control micronutrient deficiencies through supplementation and food fortification, but new approaches are needed, especially to reach the rural poor. Biofortification (enriching the nutrition contribution of staple crops through plant breeding) is one option. Scientific evidence shows this is technically feasible without compromising agronomic productivity. Predictive cost-benefit analyses also support biofortification as being important in the armamentarium for controlling micronutrient deficiencies. The challenge is to get producers and consumers to accept biofortified crops and increase their intake of the target nutrients. With the advent of good seed systems, the development of markets and products, and demand creation, this can be achieved.

/pdf/biofortification-of-staple-food-crops-1mo49sa8rw.pdf

Biofortification of Staple Food Crops

Micronutrient malnutrition, the so-calied hidden hunger, affects more than one-half of the world's population, especially women and preschool children in developing countries. Despite past progress in controlling micronutrient decencies through supplementation and food fortification, new approaches are needed to expand the reach of food-based interventions. Biofortification a new approach that relies on conventional plant breeding and modern biotechnology to increase the micronutrient density of staple crops, holds great promis for improving the nutritional status and health of poor populations in both rural and urban areas of the developing world. HarvestPlus, a research program implemented with the international research institutes of the CGIAR, targets a multitude of crops that are a regular part of the slaple-based diets of the por and breeds them to be rich in iron, zinc, and provitamin A. This paper emphasizes the need for interdisciplinary research and addresses the key research issues and methodological considerations for success. The major activities to be undertaken are broadly grouped into research related to nutrition research and impact analysis, and research considerations for delivering biofortified crops to end-users effectively. The paper places particular emphasis on the activities of the plant breeding and genetics component of this multidisciplinary program. The authors argue that for biofortification to succeed, product profiles developed by plant breeders must be driven by nutrition research and impact objectives and that nutrition research must understand that the probability of success for biofortified crops increases substantially when product concepts consider farmer adoption and, hence, agronomic superiority.

HarvestPlus: Breeding Crops for Better Nutrition

http://eprints.icrisat.ac.in/40/1/Biofortified_crops_to_alleviate_micronutrient_malnutrition.pdf

Wolfgang H. Pfeiffer

Papers

Biofortification of durum wheat with zinc and iron

Biofortification: A New Tool to Reduce Micronutrient Malnutrition

Biofortification of Staple Food Crops

HarvestPlus: Breeding Crops for Better Nutrition

Biofortified crops to alleviate micronutrient malnutrition