A 20-year study that tracked both identical and fraternal twins who were separated at early ages revealed the stunning extent to which genes play a role. Yes, genes play a role even in spiritual and social attitudes which were previously thought to be the influence of environment. This whole "nature-nurture" thing has been turned on its ear!
The most fascinating set of identical twins in the study were separated at age 4 weeks. At the age of 39, they were reunited. As it turns out, they were both named Jim by their adoptive parents, both had chronic tension headaches, bit their nails, smoked the same cigarettes, drove the same kind of car and vacationed at the same beach in Florida. How does that happen? Genes! All of that programming you inherited from your Daddy and Mama and their Daddies and Mamas and so on and so on, that's how!
Other interesting findings from the study include:
- Identical twins stand the same way, but fraternal twins stand in different positions;
- Genetics have a stronger impact on sexual orientation for male twins than female twins;
- Environment affected personality for those twins raised separately, but not when they were raised in the same environment;
- Fully 70% of IQ is related to genetics and only 30% is environmental;
- "Religiosity" (tendency to be religious/spiritual) has a 50% relationship with genes;
- Happiness and a sense of well-being has a 50% genetic influence; and
- Gum health! Yes, dental health has a genetic component!
When twins are reunited, they report feeling closer to their new-found twin than they did to their best friends which suggests a strong genetic component in the bond between twins.
Research has taught us that mothers "hand down" mood disorders and fathers hand down sociopathy, Attention-Deficit/Hyperactivity Disorder and learning disabilities. Schizophrenia, autism, language processing disorders, dyslexia, depression, anxiety have strong genetic components. Alcoholism runs in families..
If you think "she's the one" or "he's the one", ask about their educational history and how they got along with their friends. Ask about any emotional issues they may have experienced as a child or teen, but don't take their word for it. Kids have a very different perception of their early lives than do their Auntie, Uncle or Grandma. Find out if they have that "weird old uncle" that just "disappeared" because that uncle's "problems" may show up in your children. Yes, it's that strong. The genetic influence needs to be strong in order to improve the survivability of the species. The weak get weaker and the strong get stronger and that's nature's plans as Darwin observed.
I had a shocking experience in my practice many years ago. I was explaining the final results of the evaluation to a child's parents. The child was psychotic and nothing in his history suggested a reason for it. Again, I asked parents about their families' history of psychiatric disorders and again, the answer was "Nobody" until this horrified look passed over father's face. He described his much older sister who had been "taken away". He had not thought of her in years and even throughout the extensive assessment, he had not thought back to her. He poignantly talked of her problems which mirrored the ones now being exhibited in his son. After a bit of time, I realized that mother was saying nothing, just staring straight ahead in shock. When she "came around", she started screaming at him, accusing him of withholding information and that "If" she had only known...Finally, she stood up, fists clenched, and exclaimed at the top of her lungs as she ran from the office that she was divorcing him. And, she did.