Is our sexuality determined by our genetics?

Nebula Genomics started with the goal of providing secure genome sequencing while empowering customers to better understand the genetics of what makes us unique. Genetics plays a key role in helping to determine many things about ourselves. From hair color to hand dominance to risk of developing heart disease, many qualities are linked to genes passed down from generation to generation. 

With the rise of genomic sequencing and genome-wide association studies, the last decade has proven that we can peer deep into the genome to discover precise regions associated with these characteristics. By scouring through the latest scientific literature, the Nebula Research Library continues to provide customers with genetic insights on a growing array of traits and diseases.

Do our genes influence our sexuality?

A long-standing question is the extent to which genetics determine sexual preferences and sexual behavior choices. This topic has long been a controversial area, with some believing in the existence of a “gay gene” that ultimately determines orientation and preferences, while others assure that the trait is purely determined by surroundings and environment. 

Previous studies have suggested that sexual preference is determined by genetics, at least to a degree. For example, a 1998 study found that same-sex sexual behavior seems to be heritable, or passed from parent to child. Another project aimed to study sexual preferences in twins. It found that identical twins, who are perfect genetic matches, are more likely to share the same sexual preferences than fraternal, or non-genetically identical, twins. 

The largest study ever to examine the genetics of same-sex behavior

Previous attempts to discover the genes responsible for this heritability of sexual preferences have not been successful in identifying candidates. A newly-released study in Science, though, aims to answer this long-standing question by performing the largest genome-wide association study of its kind. To accomplish this massive feat, researchers studied the genetic information of nearly half a million people. Then, they linked this genetic data with information the participants provided regarding their sexual preferences. For example, researchers asked participants if they ever had intercourse with a member of the same-sex and whether they were romantically attracted to the same sex.

After combining these answers with participants’ genetic data, researchers combed through the genome to find commonly occurring variants in the DNA that appeared to correlate with how a person might respond about their sexual preferences. Doing this, they identified a number of such variants that, combined, may account for up to 25% of a person’s sexual behavior choices!

Of the many variants identified across the genome, 5 stood out. These were the most significantly correlated with the study participants’ same-sex behavior choices. Interestingly, while 2 of these variants seemed to correlate with same-sex behavior in both males and females, the analysis also identified sex-specific genetic variants. It found 2 variants that seemed to be associated with same-sex sexual behavior only in males, and another variant that was specific to females. When researchers zoomed out and looked at the genes in or near which these variants are located, links to sexual behavior became more apparent. One implicated gene plays an important role in smell, a sense strongly linked to sexual attraction, and another gene works in producing hormones that affect sexual development.

This research confirms that there is no single “gay gene”, but instead sexual behavior preferences may result partly from many genes acting together. The authors estimate that genetics may explain a significant portion of same-sex sexual behavior, with the rest due to environment and other factors. While a person’s genes cannot be used to infer their sexual behavior, studies like these continue to shed light on the vast insights laying in our genome.

Curious to learn how this study relates to your DNA?

This groundbreaking study is just one example of what’s available in the Nebula Research Library, a curated collection of studies spanning a wide area of traits and diseases. From odds of feeling sleepy during the day to risk of Alzheimer’s disease, we comb through the newest scientific publications and make the latest insights into the human genome available to our users. The Nebula Library is expanding continuously as new discoveries are added every week. 

For each new discovery, the Nebula Research Library will identify the genetic variants found associated with the trait or disease, and indicate whether they are present in your genome. We will also provide a summary of the study, as well as additional resources and information to provide further insights into the new findings. 

At Nebula Genomics, we aim to provide a private and secure personal genomics service, allowing you access to your genetic information without losing ownership of it. At the same time, Nebula aims to give you the power to better understand your genome and what makes you unique. This includes the ever-expanding Nebula Research Library, along with information on your heritage and many other traits. We aim to provide a lifetime of discovery by continually adding the latest research and information, all to help you unlock the information stored in your DNA!

To begin your journey of owning your genetic data and better understanding your genes, order your kit today.

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