By 2050, the full genome of hundreds of thousands of organisms such as plants, fungi and animals would have been sequenced by scientists from all around the world. Online databases will give free access to millions of genetic and proteomic sequences, many of them coding for life-saving traits: resistance to diseases, production of medicinal proteins and peptides and nano-engineering discoveries. Using next generation gene editing techniques, those sequences will be inserted into the genomes of other organisms, including Humans. This will allow us to transform life forms as we currently know them. Medical compounds will be commonly produced using specifically designed bacteria and complete, balanced meals will be produced from single varieties of plants, thus allowing for the population growth to continue.
The Human genome will be routinely repaired and edited to make the population more resistant to diseases and more performant, both physically and mentally. Gene therapy will most likely be available for multiple conditions but it won't be as trivial as taking a pill. Probably even more complicated than taking a pill! Editing a gene is manageable but to carry that gene inside the target cells without being damaged is a more difficult task. Delivery can already be done using viruses or nano-particles as vessels. It will probably be still relatively expensive and available mainly to the richer part of the world population. The true benefits of gene therapy will become obvious when the effect is permanent, or at least long term (several years). Already now, we can, for certain conditions, alter the DNA of existing cells. However, considering that cells have a variable, limited lifespan, those changes do not last and current gene therapies are of very limited impact. We can hope that by 2050, we will have found a way to alter cell The new era of gene therapyDNA more permanently. The first generation of gene editing tools (CRISPR) shows great potential. I am quite confident that the fourth and fifth generation of gene editing tools will be used more commonly on human beings to bring long term / permanent, beneficial changes to individuals.
Will the changes of the genome be inherited by children? That's difficult to say. To be inherited by children, the gametes need to be edited as well and that will involve a whole new level of complexity. Gene therapy will first target specific types of cells in specific organs (e.g. Hepatic stellate cells in the liver, leukocytes) and it's only much later that we might be able to edit the complete genome of an individual. Will it be done by 2050? Probably not (I would imagine that this will take more than 30 years to develop and commercialise).