The Genes For Love
- genetics
- mhc
- attraction
- chemistry

Genes positioned in the Major Histocompatibility Complex (MHC) play a key role in our immune responses, and even our relationship choice. Human populations naturally maintain diversity in these genes through mate choice — our bodies are guided by our senses to find someone we genuinely connect with.
The Genes For Love Are Located Within The Major Histocompatibility Complex
Scientifically speaking, "Romantic Chemistry" or "Sexual Chemistry" is determined by the Major Histocompatibility Complex (MHC), a group of proteins that pepper the surface of your cells and help your immune system recognise and fight pathogens.
The MHC genes are also known to influence mate-choice in many vertebrates, and variations in the DNA code of MHC genes are known to influence human partner choice. The "sweaty t-shirt" experiments demonstrated that MHC influences both body scent and body-scent preferences in humans (Wedekind et al., 1995; Kromer et al., 2016) — people with very different MHC genes tend to find each other's scent pleasant, while people with similar MHC genes find each other's scent repulsive.
Opposites do attract.

A study in an Asian American population found that MHC-based attraction (a.k.a. "Romantic Chemistry") is just as important as personality type when predicting second-date offers (Wu et al., 2018).
MHC genes also play a role in partner choice in other vertebrates. A fascinating study in obligate pair-living lemurs showed that couples with mismatched MHC genes tend to make extra-pair partner selections — the cause of "lemur affairs" (Schwensow et al., 2008).
MHC compatibility is so important that scientists have proposed humans invented kissing as a way to test for chemistry, and this biological phenomenon can even help explain the strength of the female orgasm (Sherlock et al., 2016).
In real life
Your sense of smell is your natural radar to detect romantic chemistry in person — so a good place to meet a romantic life partner is actually your local gym.
Alternatively, go online and try the DNA Romance dating app to unlock information hidden in your DNA and see predictions of sexual chemistry between you and your matches today. DNA Romance is easy to use — simply upload your raw autosomal DNA data file and within ~2 minutes your matches will be ready.
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