The yes answer- Genes are blueprints that are used in making the body’s proteins. The proteins are the molecular building blocks whose assembly provides for the cells, our physical traits and our behavioral expression. Between 3 and 5% of humans arrived on this planet with gene blueprints that are defective, specifically alterations in their genetic code distort the protein blueprint’s message and the resulting proteins made from those genes are defective. These people collectively express “birth defects,” meaning their dis-ease is derived from genes altered before birth. Yes, these people have the potential and likelihood of having their health or behavior negatively impacted by these defective genes.
The no answer- The new science of ‘epigenetics” is the science of how the environment and our perceptions of the environment control our genes. Using epigenetic mechanisms, the read-out of every gene can be modified so that a single gene blueprint can provide for over 30,000 different proteins. Epigenetic mechanisms can alter the readout of a good gene and create the equivalent of mutated proteins even though there is nothing wrong with the genes. In fact, this epigenetic mechanism is the primary way that cancer is created since most cancers (~95%) are not the result of mutations in the DNA. But in the same way that epigenetics can modify and disrupt the blueprint of of a good gene, epigenetic mechanisms would also be able to modify the product of a mutant gene blueprint and create a healthy protein. So it is possible that a person with a birth defect may override their mutation and have a normal life.