By the year 2100, will any jurisdiction enforce requirements for all births to be genetically engineered?

Our genes are the biologically encoded information from which we are built. Important traits known to be affected by our genes include aspects of intelligence and mental illness. Many physical traits, such as height, attractiveness, strength, and even longevity likewise strongly depend on the genes we have.

As the human genome and related human biological areas of inquiry became better understood, genetic engineering has become known. In the case of traits affected by simple genetic factors, it has been possible for years to change these genes, and the resulting trait(s) expressed, by means such as CRISPR/Cas9.

The pace of genetic engineering research, as measured by papers published worldwide, shows a clear trend to be growing. There is every reason to believe that as a result of this research trend, genetic engineering technology will tend to become safer, more powerful, and less expensive with time.

Human reproduction as we typically know it results in one's genes constituting a mixture of two previously existing humans' genes which were themselves selected in this manner and so on. Artificial means of reproduction still rely on the bulk DNA transfers from existing humans. Presently, genetic engineering for new humans is exceptional, as well as taboo.

The gaussian distribution of genetic traits means that most humans won't have the most advantageous genes in most areas. Further, rather undesirable traits are ubiquitous: we all age.

If genetic engineering reaches the level where it is possible to safely and reliably eliminate the possibility of traits widely considered undesirable, such as predisposition toward schizophrenia, cystic fibrosis, or intellectual disability, there is good reason to think that humans may consider such genetic modification an ethical imperative. This is one scenario.

Human intelligence is one of the most complicated constructs of substantial genetic determination. Even so, it is possible that humanity could come by a sufficient understanding of the relationship to set humans-to-be with brains optimized to be as smart as possible. It may not be so easy to reach a consensus recognizing these types of modifications as ethnically necessary.

Of course, it goes on. Any desirable trait controlled by genetics can in principle be added by genetic engineering, and any undesirable trait removed. Consequently, the space for possible legal mandates in this field is immense.

On environment: redwoods have genetics to grow very tall, but if you take one to the desert, it won't work very well (or at all). So while environment interacts with genes, the genes provide the foundation for what the environment has to work with.