It takes years to develop high performing crops and animals, and efforts in sub-Saharan Africa and South Asia have fallen behind. However, powerful new tools are emerging that can help speed improvement in plants and animals. Using genomic technologies—those that examine the entirety of available genetic diversity in individual plants or animals and populations of those individuals—scientists can identify beneficial genetic traits and bring together new combinations of genes that enable crops and animals to perform well in specific environments.
Tier I Technologies
Annotated crop genomes (describing their genetic details)
There is a need to establish baseline information about the genetic diversity of local crops in the two regions. Annotation of genomes—determining the genetic sequence and gene functions—of plants that are important to farmers in these regions would help speed crop improvement. Given advances in the rate of DNA sequencing, the full genetic code of key crops grown in the two regions could be built very quickly, and the identities and function of their genes could be determined by relying on similarities to the existing Arabidopsis, rice, and sorghum sequences and the emerging maize sequence. A variety of genomic tools can then be used to analyze how the plants’ genes function in different environments.
Genome-based animal breeding
Genomic tools can also be used to help animal breeders increase the quality of their livestock. It is feasible to generate reference genomes (genetic sequences that can be used to study and compare animals’ genetic traits) for Bubalus bubalis—the Asian water buffalo—and other farm animals raised by subsistence farmers in the regions, such as goats and hair sheep. By taking samples of DNA from many animals throughout each region and observing and recording their traits (“good milk producer,” for example), breeders would get a picture of the genetic diversity in the whole population of animals. By associating the DNA with the traits, breeders can construct the theoretical genetic pedigree of a farm animal with the most desirable traits. Armed with this information, conventional breeding methods can go forward at a much faster pace.
Tier II Technologies
Site-specific gene integration
Currently, new genes can be added to a plant for improved performance, but they are incorporated in a random fashion, and they often bring along linked genes that negatively affect the performance of a crop. A technology that would fulfill the dream of crop breeders to replace one gene with another in an exact location is called site-specific gene integration. This tool would allow breeders to more precisely and reliably control the genetic makeup of crops.
Spermatagonial stem cell transplantation
For animal improvement, one of the biggest hurdles is getting the right genes distributed throughout the herd. But a new approach is to harvest spermatogonial stem cells (which give rise to sperm cells) from genetically superior males and transplant them into many other males, who then distribute those genes to the females they encounter. This approach would circumvent the technical difficulties currently posed by artificially inseminating females.
Microbial genomics of the rumen
No matter how good its genetics, an animal that is poorly nourished cannot fulfill its production potential. Further investigation of the microbial diversity of the rumen (the multi-chambered stomach of cattle where microorganisms play a key role in digestion) could lead to methods that enhance animals’ ability to extract nutrients from difficult-to-digest grasses that are the predominant animal foods in the two regions.