Men and Women’s Different Biology Supports Their Different Roles

We see examples of this in stores where clothing is no longer designated as men’s OR women’s and toys are no longer boy’s OR girl’s. We see it in sports where biological men are allowed to compete against biological women because the men “identify” as women. Courts are ruling that the male-only military draft may not be constitutional. A lawyer representing the National Coalition of Men said, “Either they need to get rid of the draft registration or they need to require women to do the same thing that men do.”1 At the 2023 American Anthropological Association (AAA) conference, a session about skeletal differences between males and females was canceled because it was considered “transphobic.” The AAA stated, “There is no single biological standard by which all humans can be reliably sorted into a binary male/female sex classification.”2 As a PhD geneticist, I can confidently say this is scientifically absurd, and as a Christian, I can say it’s biblically wrong as well.

Men and Women: Equally Valuable, Differently Gifted

God created males and females equal—but different. That’s not to say we don’t have some sameness. We both bear the image of God (Genesis 1:26–27). We both are sinners in need of salvation (Romans 3:23), and when we receive Christ as our Savior, we are one in Jesus (Galatians 3:28). But we are also different!

Women and men are both made in the image of God, but we have unique character qualities that cause us to bear that image differently.

Women and men are both made in the image of God, but we have unique character qualities that cause us to bear that image differently. Women tend to be caring and nurturing. God displays this characteristic vividly in Matthew 23:37, where Jesus speaking of the Israelites says, “How often would I have gathered your children together as a hen gathers her brood under her wings.” Men tend to be protectors and fight to protect those in their care. God displays this characteristic in Isaiah 42:13 where Isaiah says, “The Lord goes out like a mighty man, like a man of war he stirs up his zeal; . . . he shows himself mighty against his foes.” Women and men bear God’s image differently and that is part of God’s good design. We are equal but different. I’m not saying that certain character qualities of God are exclusive to one sex or the other, but we tend to see certain characteristics more often or more clearly in one sex than the other, and that is good!

Men and women also have different functions and roles especially within marriage and the church. God created Eve as a helper to Adam (Genesis 2:18), and wives are to submit to their husbands (Ephesians 5:22). This doesn’t imply an inferior/superior relationship within marriage; rather, it reflects different roles. We see this reflected in the Trinity as Jesus submits to the Father yet is equal to the Father. Husbands are to love their wives as their own bodies and as Christ loved the church by dying for her (Ephesians 5:25–28). These different roles are an earthly reflection of the heavenly reality of the relationship between Christ and the church (Ephesians 5:32). Again, men and women are equal but different, and that is good!

Differences in Biology and Genetics

Men and women are also biologically unique, and sometimes, we can even see directly how that biological design is related to our different character qualities and functions/roles. God’s design is truly purposeful! In this article, we’ll explore some of the genetic and cellular differences between men and women.

Contrary to what the AAA said, there IS a “single biological standard by which all humans can be reliably sorted into a binary male/female sex classification.” It’s called our sex chromosomes. Females have two X chromosomes, and males have one X and one Y chromosome. I have an easy saying to help people remember this: “No Y, no guy!” The Y chromosome has the sex-determining region Y gene (SRY for short) that inhibits female anatomical growth and induces the formation of male anatomy during embryo development. Some will argue there are sex chromosome abnormalities that make sex determination at birth or even puberty challenging. While these abnormalities are real in our fallen world (and these parents and children need compassion and support), it is never right to argue for normal from the abnormal.

Many of the genes on the Y chromosome (like SRY) are unique and don’t have any “match” on the X chromosome. But there are some genes for basic cellular functions that exist on both the X and Y. Genes for basic cellular functions usually do not differ much within the human population because these are functions that all human cells must perform for people to live. However, scientists have discovered a gene, named RPS4, that has different versions on the X and Y chromosomes.3 This gene has the instructions for a ribosomal protein, and ribosomes assemble proteins in our cells. This means that male and female ribosomes are different. This blew my mind! The biological classification of mammals, which includes humans, don’t really differ much in their ribosome makeup, yet God has seen fit to design male and female humans with different ribosomes. Why? I have no idea! I’m excited to see more research that determines why this difference is important.

Although females have two X chromosomes, one of them is “inactivated.” Males only have one X chromosome and females in essence only have one active X chromosome—or so we thought. It turns out that 15–23% of the genes on the so-called “inactive” X may still be active in that proteins are made from the genes.4 Many of those genes are thought to be related to the immune system, and as a result, women may have a more robust immune system. Women have higher circulating numbers of white blood cells and nearly every immune system response in females is higher.5 This relates well to a woman’s function/role in caring for children who often harbor a lot of germs! Also, women tend to have the character quality of being social and being in groups of people more often than men. The gene activity on the “inactive” X may offer a protective mechanism against exposure to harmful bacteria and viruses often found in these social interactions. It also may mean that “man flu” is a real thing!

“True equality is about respecting difference, not trying to erase it . . . ”

A 2017 gene activity study looked at 18,000 genes in 45 tissues to see if there were differences in activity between males and females.6 The researchers expected only a few hundred of these genes would show a difference. However, they found a whopping 6,500 genes (1/3 of those studied) have different activity levels!7 Some genes are active in men or women only, while some are much more active in one sex or the other. Much of the difference in activity levels is thought to relate to sex hormone differences. Testosterone in males and estrogen/progesterone in females likely causes genes to be “read” differently, resulting in different outcomes. One journalist in discussing these differences said, “True equality is about respecting difference, not trying to erase it . . . . To be equal, men and women don’t have to be the same. Which is just as well, because they’re not.”8 Equality of the sexes should not, does not, and cannot mean sameness on a biological (or biblical) level. Thinking otherwise can have dangerous repercussions.

Differences in male/female genetics and their outcomes play a significant role in disease development, diagnosis, and treatment. For example, in males, fatty deposits in coronary arteries tend to be at specific locations, whereas in females, the deposits tend to line the artery more evenly, which makes heart disease harder to detect in females.9 Often, women are not included in clinical trials for the study and treatment of disease. This may explain why drugs that are effective at treating disease in men sometimes do not work in women. It’s very likely that men and women metabolize drugs differently (because of sex chromosome and sex hormone differences), and what is an effective treatment in one sex may not be in the other.

Every Human Cell Has a Sex

Dr. Paula Johnson, founder and former executive director of the Connors Center for Women’s Health and Gender Biology, stated, “Today, we know that every cell has a sex. . . . And what it means is that men and women are different down to the cellular and molecular level. It means that we’re different across all of our organs, from our brains to our hearts, our lungs, our joints.”10 Yes and amen! In part 1, we’ve learned some of many, many genetic and cellular differences between males and females. In part 2, we’ll delve into the anatomical and physiological differences to understand more about how God’s unique biological designs of men and women relate to their character qualities and functions/roles. It truly is purposeful design!