Instant Chemistry uses Biological and Psychological Factors to Determine Relationship Compatibility

The Basics of Relationship Compatibility

Now, with advancements in relationship science, DNA can be used to help you and your partner improve your relationship. Instant Chemistry has developed a method for assessing relationship compatibility based on scientific principles - a combination of genetics and psychology. We now have a deeper understanding of what makes relationships successful and are continuing to learn more every day. This research has come from academic institutions around the world and has been published in numerous peer-reviewed journals.

Our genetic and psychological tests allow you to analyze your compatibility with your partner in a safe, private, and cost-effective way. Recent research has shown that biologically compatible partners are more physically attracted to each other, experience longer lasting relationships, and have better sex lives. Instant Chemistry can help give you insights into how your relationship ticks and where strengths and weaknesses may lie. Go ahead and learn about your relationship and help it grow.

Percentage Compatibility


In a landmark study led by Dr. Claus Wedekind of University of Lausanne, Switzerland in 1995, women were asked to smell shirts worn by men and rank them. They consistently ranked men with HLA genes unlike their own as more attractive. Since this publication, many other studies have confirmed that up to 40% of physical attraction can be determined through our genes alone. There is now strong scientific evidence that biologically compatible partners enjoy greater attraction to one another and have superior relationship stability.

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 partner (1,2,3,4). 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 infections (5). 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 stability (1,6), increased fertility rates (7,8), and find each other more attractive (1).

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 compatibility (9). These genes help identify foreign entities in our bodies, such as bacteria causing infections. These genes also contribute to creating our unique body scent (9). Research shows that we subconsciously detect how similar or different another person’s immune system is from our own through their body scent (10,11). These instinctual preferences strongly affect human attraction and help us chose our romantic partners.


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. In addition, your desire to seek out new sensations and experiences can be influenced your brain’s sensitivity to a hormone called dopamine. 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.

Emotional Compatibility Genes

Serotonin Transporter Gene The serotonin transporter gene moderates the association between negative and positive emotional behavior and changes in marital satisfaction over time (12). For individuals with two ‘short’ versions of the transporter, higher negative and lower positive emotional behavior at the beginning of a 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

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 gene (13). It is interesting however, that the way we live our life impacts the effect of this gene on our social and emotional behaviors (14). 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

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 lovers (15,16,17). Individuals with DRD4 7R have also been found to lose their virginity sooner, have children at an earlier age, and come from more multi-racial backgrounds (18). 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 we up to 20% more likely to take financial risks (19). 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 function (20,21). Executive function is an umbrella term for cognitive functions such as, reasoning and problem-solving. They also experience less pleasure out of daily life (22). 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 anxiety (23). People with the Met version of the gene are known as worriers because they tend to have higher anxiety (23) 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 gene (23). However, people with the ‘Met’ version of the gene tend to be more creative, get more pleasure out of life (22), score better on tests of executive function (20,21) and are often better at reading comprehension.

Psychological Compatibility

Psychological Compatibility
Instant Chemistry uses a psychological instrument specifically designed for profiling behavioral patterns in four well-researched dimensions of relationships. The goal is to determine interpersonal compatibility in the most efficient and effective manner possible. Completing the test generally requires 10-15 minutes at most. The test creator is award-winning psychologist Dr. Joel Block, a renowned clinical psychologist specializing in couple therapy. Dr. Block is Board Certified in Couple therapy by the American Board of Professional Psychology, and a senior psychologist on the staff of the North Shore-Long Island Jewish Medical Center and an Assistant Clinical Professor (Psychology/Psychiatry) at the Hofstra North Shore-LIJ Medical School. For twenty years he was the training supervisor of the Sexuality Center at Long Island-Jewish Medical Center. Dr. Block is the author of over 20 books on Love and Sex, his specialty.

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10. Milinski, M, et al. Major Histocompatibility Complex peptide ligands as olfactory cues in human body odour assessment. Proc Biol Sci 280(1755) (2013)

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12. Haase, C. et al. The 5-HTTLPR Polymorphism in the Serotonin Transporter Gene moderates the association between emotional behavior and changes in marital satisfaction over time. Emotion 13(6) (2013) 1068-1079

13. Rodrigues, S.M. et al. Oxytocin receptor genetic variation relates to empathy and stress reactivity in humans. PNAS (2009) 106(50) 21437-21441

14. Kim, H.S. et al. Culture, distress, and oxytocin receptor polymorphism (OXTR) interact to influence emotional and support seeking. PNAS (2010) 107(36) 15717-15721

15. Benjamin, J., et al. (1996). Population and familial association between the D4 dopamine receptor gene and measures of novelty seeking. Nature Genetics, 12, 81–84.

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17. Zion, I.B., et al (2006). Polymorphisms in the dopamine D4 receptor gene (DRD4) contribute to individual differences in human sexual behavior: desire, arousal and sexual function. Molecular Psychiatry, 11, 782-786.

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19. Dreber, A., et al. (2009). The 7R polymorphism in the dopamine receptor D4 gene (DRD4) is associated with financial risk taking in men, Evolution and Human Behavior, 30: 2, 85-92.

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21. Isomura, M.S., et al. (2013). Impact of five SNPs in dopamine-related genes on executive function, Acta Neurologica, 127:70-76

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23. Montag, C., et al. (2008). COMT Genetic Variation Affects Fear Processing: Psychological Evidence, Behavioral Neuroscience 122(4) 901-909