instant chemistry



Scientific research suggests that both genetic and environmental factors have a significant influence on our romantic relationships. Ample research suggests that dysfunctional relationships may impair your psychological and physical well-being. Thus, an improved understanding of the genetic and environmental influences characteristic of supportive romantic relationships has tangible practical value to long-term relationship satisfaction. Many genes have been associated with long-term relationship satisfaction and physical chemistry. Instant Chemistry has developed a method for assessing relationship compatibility based on examining genes related to biological compatibility and emotional compatibility. This research has come from academic institutions around the world and has been published in numerous peer-reviewed journals.


The Basics Of Human Compatibility

We all have many potential romantic partners and there are many factors that we use to find the right person – both consciously and unconsciously. Scientific research has shown that relationship markers – a combination of genetics and psychology – strongly affect who we are attracted to and how successful our relationships are.

Biological Compatibility

Scientific breakthroughs about your natural body scent demonstrate body scent, which is determined by your genes, is an important part of chemistry. We know having great chemistry with someone is an extremely important part of a successful relationship. Biological compatibility is a form of genetic compatibility between people. Couples in long-term relationships were often found to have very different immune system genes from their partner1,2,3,4. Research shows that children born to couples with very different immune system genes are more likely to successfully defend themselves against a greater variety of infections5. But not only does scientific evidence point to children with strong immune systems, the research has shown that these couples also enjoy more satisfying sex lives6, greater marital stability1,6, increased fertility rates7,8, and find each other more attractive1.

The Human Leukocyte Antigen System

Some of the genes in your immune system that will be classified in the Instant Chemistry process belong to the Human Leukocyte Antigen (HLA) system. They are located in a genetic region of chromosome #6, known as the Major Histocompatibility Complex. Although the HLA system is made up of many different genes, the three genes: HLA-A, HLA-B and HLA-DRB1 play an important role in biological compatibility9. These genes help identify foreign entities in our bodies, such as bacteria causing infections. These genes also contribute to creating our unique body scent9. Research shows that we subconsciously detect how similar or different another person’s immune system is from our own through their body scent10,11. These instinctual preferences strongly affect human attraction and help us chose our romantic partners.

Emotional Compatibility

In the beginning stages of most exciting new relationships our brain chemistry and hormone levels are far from normal. For example, your feelings of well-being and happiness are affected by a hormone called serotonin, which plays an important role in emotional responses, especially when measured against your partner. Another hormone called oxytocin affects how empathic you are to others and your ability to deal with stress. Your desire to seek out new sensations and experiences can be influenced your brain’s sensitivity to a hormone called dopamine. In addition, how fast dopamine is broken down in your brain affects your creativity and anxiety levels. Understanding your partner’s emotional behavior is the key to successfully dealing with relationship challenges, solving problems and better communication. We now have the ability to reveal vital information which would normally take years for you to learn over time with your partner.

Serotonin Transporter Gene

The serotonin transporter gene moderates the association between negative and positive emotional behavior and changes in marital satisfaction over time12. For individuals with two ‘short’ versions of the transporter, higher negative and lower positive emotional behavior at the beginning of marriage can predict declines in marital satisfaction over time. Instant Chemistry helps uncover this component of compatibility and empower individuals with ways to work with their results.

Oxytocin Receptor Gene

Oxytocin is a hormone which has broad influences on both our social and emotional behaviors. The oxytocin receptor moderates the effect of oxytocin on our body. There are many different versions of the oxytocin receptor, but two have been identified to play an important role in how empathetic we are and how we respond to stress. Individuals who are the ‘G’ version of the gene display continually high emotional empathy towards others and experience lessened stress responses compared to people who have the ‘A’ version of the gene13. It is interesting however, that the way we live our life impacts the effect of this gene on our social and emotional behaviors14. Because understanding your partner’s emotional behavior is the key to successfully dealing with relationship challenges, knowing which oxytocin receptor variants two individuals carry help empower the couple to impact their genetics by impacting their lives.

Dopamine Receptor Gene

Dopamine is a hormone which affects our cognition, motivation, attention and learning. There is a gene which helps control dopamine called DRD4. One version of the DRD4 gene called DRD4 7R gives carriers a reduced ability to respond to dopamine This gene variant is more often found in people who are extroverted impulsive, adventurous and better lovers15,16,17. In dividuals with DRD4 7R have also been found to lose their virginity sooner, have children at an earlier age, come from more multi-racial backgrounds18. Some scientists suggest that this gene variant may strongly influence risk taking behaviors in humans. One study found that men carrying the DRD4 7R gene were up to 20% more likely to take financial risks19 Ultimately, the dopamine DRD4 gene is an important gene that has been strongly associated with reproductive behavior and pair bonding in humans. Knowing which DRD4 version is more suitable to you can help you find what you’re looking for in a partner.


Catechol-O-methyl transferase or COMT is an enzyme that breaks down dopamine in the brain. Researchers have found that we carry different versions of this gene which affect how quickly our brains process dopamine. One version of this gene (‘Val’) breaks down dopamine quickly while the other version (‘Met’) does so slowly. The terms ‘Val’ and ‘Met’ are simply used to indicate the difference between the two versions of the enzyme. A person with a ‘Val’ version has a valine amino acid at position 158 of the COMT enzyme while a person with a ‘Met’ version has a methionine amino acid instead. People with the ‘Val’ version of the gene tend to score lower on tests of executive function20,21. Executive function is an umbrella term for cognitive functions such as, reasoning and problem-solving. They also experience less pleasure out of daily life22. On the other hand, carriers of the ‘Val’ version of the gene are better at handling stress and pain than people with the ‘Met’ version of the gene. They are also more resilient to negative events and experience less anxiety23. People with the Met version of the gene are known as worriers because they tend to have higher anxiety23 and lower emotional resilience to negative events. They also tend to experience stress and pain almost 6 times greater than people who only carry the ‘Val’ version of the gene23,24. However, people with the ‘Met’ version of the gene tend to be more creative, get more pleasure out of life22, score better on tests of executive function20,21 and are often better at reading comprehension.


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