#	Pagina
attuale pagina	/open-h2020/projects/195432/results.html

Report

Teaser, summary, work performed and final results

Periodic Reporting for period 1 - CaMILLET (Application of crop genetics to improve Calcium content in millets and other crops for promoting health benefits in the prevention and treatment of osteoporosis)

Teaser

Summary

Humans require more than 20 mineral elements for healthy body function. Calcium (Ca), one of the essential macro-mineral, is required in relatively large quantities in the diet for maintaining a sound overall health. Despite the importance of adequate Ca intake, the World Health Organisation (WHO) estimates that low dietary intake of Ca is common across the world (WHO, 2006). It has recently been determined (mainly based on food supply) that 3.5 billion people were at the risk of Ca deficiency in 2011, with approximately 90% of the affected individuals in Africa and Asia (Kumssa et al., 2015). Young children, pregnant and nursing women in marginalized and poorest regions of the world, are at highest risk of Ca malnutrition. Elderly population is another group of people most commonly affected by Ca deficiency mainly in the form of osteoporosis and osteopenia.
Improved dietary intake of Ca may be the most cost-effective way to meet such deficiencies. As large segments of these populations are typically dependent on what they grow and produce for their Ca need, staple crops that can offer adequate Ca requirements, especially for people of low income groups, offer an excellent and sustainable solution. Among all cultivated cereals, finger millet [Eleusine coracana (L.) Gaertn.], an annual small millet of Africa and Asia, has the highest concentration of Ca (350mg/100g) in its grains and can serve as an excellent sustainable candidate for Ca biofortification. It has three times more Ca than milk and 10-fold higher Ca than brown rice, wheat or maize (Kumar et al., 2016a). Besides Ca, finger millet is also very rich source of iron, amino acids like methionine, slowly digestible starch and phytochemicals like polyphenols. It is a gluten-free, low fat cereal which is non-allergic and easily digestible. Apart from its nutritional attributes, finger millet has excellent environmental sustainability credentials. It can easily withstand harsh climatic conditions, low soil fertility, requires very little inputs with a short growing season (Kumar et al., 2016a). It can reach the yield potential of up to 10 tons/ha under optimum irrigated conditions (Padulosi et al., 2015). It has excellent storage quality traits and can be valuable in areas where farmers suffer losses due to dearth of post-harvest management. For these characteristics, it is often termed as a â€œsuper cerealâ€ (Kumar et al., 2016a). Therefore, a better understanding of the genetic basis of grain Ca accumulation in finger millet will offer an improved strategy for Ca biofortification breeding programs. However, so far limited genetic and genomic studies have been conducted in finger millet.

Work performed

A collaboration with ICRISAT, Kenya provided us access to core, mini-core and elite local genotypes of finger millet having diverse geographic origins and representing the entire genetic variation of the germplasm. From this, we selected a set of 190 accessions with diverse geographic origins to develop a genome-wide association study (GWAS) population. The project initially only aimed to investigate the genetic variations of Ca accumulation in finger millet germplasm using chemical phenotyping and genomics. We later expanded the objectives to also investigate the extent of genetic variation for other important micronutrients such as iron, zinc, sodium, potassium, and magnesium as well as the macronutrient protein present in this grains of finger millet. This is because finger millet is also a rich source of essential micronutrients, the deficiency of which affects almost 2 billion people across all age-groups and genders and is endemic to both developing and developed countries.
The multi-element and total protein analyses in the ground seed samples revealed large phenotypic variation in the various genotypes (Attached image). Therefore, some genotypes having particularly high Ca, Fe, Zn and protein contents have been identified through the work. Using DNA extracted from 190 genotypes and large-scale genotyping-by-sequencing followed by a preliminary post-processing of GBS data by (minor allele frequency > 0.01 and missing data per site < 90%), 156,157 SNPs have been generated from this panel. From these, > 50000 usable SNPs were employed to conduct a GWAS. Through this, genomic regions associated with these micronutrients and protein have been uncovered which will help to identify underlying genes once the finger millet whole genome sequence is released.

Final results

The long-term aim is to develop calcium-rich finger millet. As an initial step in this direction, the project has identified more than a million genetic variations (single-nucleotide polymorphism) in the finger millet germplasm that have been assessed to see if they are linked with higher calcium content for the first time. In addition, the markers have been used for correlations with iron and zinc, which are other important micronutrients to address micronutrient malnutrition.
The project has allowed to establish collaborations with in Kenya and India- regions where finger millet is a staple for millions of people, including some of the poorest and marginal farmers. By employing these results in conventional genomics-based breeding, finger millet varieties that contain higher levels of calcium and other micronutrients will be developed, without using genetic engineering. In addition, using the syntenic relationship among cereals, the results hold promise for improving the nutritional profile of traditional cereals like rice or wheat. Therefore, the project strongly impacts in improving nutrition right from the farmerâ€™s field benefiting farmers and their families, in both economic and nutritional manner. Ultimately these product developed from these calcium-rich crops should have an impact in lowering rates of osteoporosis and calcium malnutrition in children or pregnant and lactating women.