Binary biological sex – male and female – is a truth made clear in Scripture. Genesis 1:27 states, “God created man in His own image, in the image of God He created him; male and female He created them.” This verse has long been interpreted to affirm the existence of two distinct sexes – male and female.
However, in today’s society, the once-clear distinctions between male and female are now blurred. Recent surveys have highlighted the growing visibility of transgender and nonbinary people (those not identifying with either male or female definitions). Even in the scientific community, there is a hesitation – if not an outright refusal – to acknowledge the differences between the biological sexes.
For example, at its annual meeting in 2023, the American Anthropological Association (AAA) canceled a session that aimed to explore biological sex as an analytic category in anthropology. The AAA justified its decision by stating that “there is no single biological standard by which all humans can be reliably sorted into a binary male/female sex classification.”
The 2024 Olympics also brought these issues to the global stage when the gender eligibility of athletes came into question because their biological sex differed from their sexual “identity.”
It’s obvious the culture is immersed in the debate around gender identification and biological sex, and whether these things are the same or can even be defined. So, to illuminate these complex issues through a scientific and biblical lens, The Stand spoke with Dr. Georgia Purdom, a Christian molecular geneticist specializing in cellular and molecular biology. She currently serves as the vice president of educational content at Answers in Genesis (answersingenesis.org). Here is what she had to say:
The Stand: Is biological sex a concrete fact or open to interpretation?
Georgia Purdom: From a genetic standpoint, biological sex is determined by our chromosomes. I often say, “No Y, no guy.” Females typically have two X chromosomes, while males have an X and a Y chromosome. This chromosomal distinction provides a clear biological marker for sex. It’s important to note that sexual development disorders do occur, and we must approach these situations with compassion. However, chromosomal analysis remains a reliable method for determining biological sex.
TS: What are some key biological differences between males and females that science has identified?
GP: The differences between men and women go beyond the obvious [and are] rooted deep in our genetics and show up in various physical ways. This is especially clear in sports competitions. Men usually have bigger muscles, stronger bones, larger lungs, and more powerful cardiovascular systems. This means that even average male athletes can sometimes outdo top-tier female athletes in certain sports.
TS: Can you explain some of the differences in genetics between the biological sexes?
GP: A 2017 study found that over 6,500 genes out of our approximately 20,000 show different activity levels in male and female tissues. This differential gene expression contributes to the biological distinctions between sexes.
Interestingly, recent research has challenged previous assumptions about gene activity in females. While it was once thought that one of the two X chromosomes in females was largely inactive, we now know that about 23% of the genes on this “silent” X chromosome are actually active. Many of these genes are involved in immune function, which may explain why women often exhibit stronger immune responses and disease resistance compared to men.
TS: How do “gender-affirming” treatments interact with the body’s natural hormones and genetics?
GP: This is an area that requires extensive research. When we introduce hormones that contradict the body’s natural production – for example, administering testosterone to a female body that naturally produces estrogen – we’re essentially conducting a large-scale experiment.
We’re already observing some concerning outcomes, such as decreased bone density in young women undergoing these treatments, and alterations in brain development and connections.
Hormones play a crucial role in gene expression, influencing which genes are active or inactive in different tissues. When we artificially alter hormone levels, we’re not just changing physical characteristics; we’re potentially altering the function of thousands of genes throughout the body.
For example, estrogen and testosterone have significant effects on bone density, muscle mass, fat distribution, and even cognitive functions. Blocking the body’s natural hormones and introducing cross-sex hormones can have wide-ranging effects on these systems.
TS: Would you say that there is no room, scientifically, for confusion when it comes to biological sex?
GP: Yes. Every cell in the human body, except for red blood cells, is genetically male or female due to its chromosomal makeup. This genetic distinction influences sex hormone production and gene regulation throughout the body. These differences extend to brain structure and function.
For example, women typically have more neural connections between brain hemispheres, while men have more connections within each hemisphere. Such variations also affect how medications interact with the body, highlighting the importance of including both sexes in medical and drug studies.
We are all created in God’s image, regardless of biological sex. However, our cellular sex is an intrinsic part of our physical being and influences many aspects of our physiology and identity.
For those struggling with gender identity issues or born with intersex traits, it’s crucial to approach them with compassion. As Christians, we believe true wholeness comes through a relationship with Jesus Christ. Our role is to share this message of hope lovingly, helping individuals understand there is purpose in embracing their God-given identity.
(Digital Editor's Note: This article was published first in the December 2024 print edition of The Stand. Click HERE for a free six-month subscription.)
