I’m a genetics professor with a Hindu background, Indian ancestry, American citizenship, and Christian beliefs. Am I more than my genes? Absolutely. And, I believe, so are you. I hope you find in my story the encouragement to wrestle with the hard questions of life, and not to be satisfied with easy answers that do not reach into the depths of who we are and why we’re here.
The word “genome” suggests to many that our DNA is simply a collection of genes from end-to-end, like books on a bookshelf. But it turns out that large regions of our DNA do not encode genes. Some once called these regions “junk DNA.” But this was a mistake.** More recently, they have been referred to as the “dark matter” of our genome. But what was once dark is slowly coming to light, and what was once junk is being revealed as treasure. The genome is filled with what we call “control elements” that act like switches or rheostats, dialing the activation of nearby genes up and down based on whatever is needed in a particular cell. An increasing number of devastating complex diseases, such as cancer, diabetes, and heart disease, can often be traced back, in part, to these rheostats not working properly. What’s more, environmental variables – like diet – can influence the way that genes and their rheostats work, thereby altering genome function and cell behavior, without making changes to the underlying DNA sequence at all. So, we cannot reduce an individual to a set of genes, or even an entire DNA sequence, rheostats and all, because how that DNA works depends, at least in part, on the environment as well.
Beyond human DNA
A remarkable discovery in biology in the last decade is that the human body is home to trillions of microorganisms, predominantly bacteria. Trillions. This is a staggering number. In fact, based on the most recent conservative estimate, more than 50% of the cells in our bodies have bacterial, not human, DNA. These bacteria live alongside and communicate with our human cells in a variety of organs, including the skin, the lung, and the intestine, and it turns out that they are essential for the healthy functioning of those organs. For example, microbes in our gut are critical for controlling how we absorb nutrients from the food we eat and how we maintain energy balance throughout the day. Some scientists are beginning to suggest that gut microbes may contribute to our mood and even how we learn and make memories. Changes in the bacteria can dramatically alter the way our human cells work, without making any changes to our DNA sequence at all, and this could lead to altered human behavior, and various diseases, such as diabetes, cancer, and even mental health conditions. So the bacteria in our body obliterate the view that humans are defined entirely by our own DNA. Our biological identities are closely wrapped up in bacteria!
Truth beyond science
So far, in this discussion of human identity, I’ve been focused on the science. But is science the only way of knowing? Is it the sole arbiter of truth? There is a common misconception that scientific explanations are exclusive: if I’ve understood something scientifically, I’ve understood it fully. Science offers a set of powerful tools for answering “what” and “how” questions about the natural world, but it does not have the tools to answer the big “why” questions of meaning and purpose. This does not by itself mean that there are answers to the “why” questions elsewhere – but it does mean that we have to be faithful to what science is, and not extend its purview beyond what it is capable of addressing. Science is necessarily agnostic with respect to anything outside of the natural realm. It neither accepts it, nor can it refute it. Therefore, the important point here is that science does not constrain us to look only to science in our search for the complete truth about who we are. So, beyond a scientific explanation of who I am, including genes, rheostats, environment, and bacteria, where else might I look to define my identity? Perhaps my name is a good starting point.
My name, Praveen Sethupathy, is of Sanskrit origin. Praveen means “skillful.” Sethupathy means “lord of the bridge.” The bridge refers to a chain of limestone shoals that connected the southern tip of India to the northern coast of Sri Lanka. According to the ancient Hindu epic, “The Ramayana,” the bridge was constructed by lord Rama – an incarnation of the Hindu god Vishnu – and his army. My name is steeped in ancient Indian tradition and Hindu lore and my Indian heritage is an important part of who I am. I was raised as a Hindu for eighteen years and have always appreciated Hinduism as a rich culture to enjoy. But it wasn’t until my college years that I realized I didn’t really know much about Hinduism as a belief system to live by. I had gone through the motions of various rituals and was familiar with many of the traditions and stories of the faith. But I had no idea what Hinduism meant to me. I hadn’t really stopped to think about it.
An unlikely hero
As a curious undergrad at Cornell University, I embarked on an ambitious endeavor to read the Hindu Scriptures. But as I learned more about Hinduism, I became curious about how it compared to the host of other world religions. Eventually, I studied the major texts from many other religions, including Buddhism, Islam, and Christianity. What was it that stood out for me in Christianity? It was meeting the unique person of Jesus. He’s the supposed hero of the story, but he’s naked and broken on a cross. It seemed the opposite of a hero at first. But what I would learn is that he wasn’t on the cross because he was powerless to stop it. He was on the cross because that’s precisely how he chose to exercise his power – laying his life down solely for the sake of others. As a Christian, one who claims to follow in the way of Christ, I am also called to live a life of self-sacrifice for the benefit of others. The Scriptures say, “Let each of you look not only to his own interest, but also to the interest of others.” I don’t always live up to that calling, but it really does shape the way that I think about who I am. The Christian call is not to be safe and sound, bunkered within the confines of our walls. No, it’s to be willing to risk ourselves for the life and dignity of others. It is to consider the interests and needs of others even if it compromises our own safety or comforts. I am not compelled to this ethic merely out of logic, science, or reason, but by my faith in who Christ is, what he has done for me, and the example that he sets for me. Service toward others is not what we do when we want to feel good about ourselves or because it’s merely an evolutionary mechanism to benefit our “selfish genes.” I believe it’s what we do when we understand what it really means to be human.
Evaluating the evidence
As a biologist, I’ve learned that biological science is very rarely about “proof.” It’s more like detective work: accumulating evidence toward the most reasonable or likely explanation. So when I started getting interested in Christianity, I started evaluating the historicity of the gospel accounts of Jesus’ life. I did this much in the same way I carry out scientific work: gather data, make inferences, and make the case for the most likely scenario. Why was this so important for me to do? Stripped of Christ, Christianity was no more or less compelling to me than any other faith tradition. It was the person of Jesus that made all the difference.
Finding my identity
When I started following Jesus and finding my identity in him, it was a very confusing time for my family. Was I rejecting my Indian culture? Would I change my name to John or maybe Peter? Their confusion was not unfounded: many before me had done exactly that. But Jesus did not come to change names or to move people from one culture to another. He came to renew hearts and minds, and to bring life where there was death. So it was my joy to share with my family that I would remain Praveen Sethupathy—that Christ was laying a claim on my heart, not on my name. Becoming Christian had nothing to do with rejecting my Indian heritage. Rather, it was about embracing God’s interwoven presence in the history of mankind, Christ’s love and sacrifice for us, and our desperate need for him. Christ was brewing within me a renewed sense of purpose, commitment to others, and passion for justice.
Faith and culture
My Hindu heritage is part of who I am, a part of who I believe God created me to be. Perhaps you feel the same about your cultural background. But our culture and our core beliefs too often get confused as the same thing. Just as our bodies are not fully determined by our genes, so our identity is not dictated solely by our cultural background. If, like me, you come from a non-western background, don’t be put off by the misconception that Christianity is a western religion: it isn’t. Christianity began as a movement of Palestinian Jews. The first African convert to Christianity is recorded in the New Testament book of Acts. The Christian movement in India traces its roots back to the second century. And today, there may be more Christians in Asia and Africa than in Europe and North America.
Keep an open mind
No matter how popular the view of “junk DNA” among some in the scientific community, there was still an openness to the possibility that there was much more to it. In your search for identity, I would challenge you to ask yourself the hard questions and consider possibilities you may have always discounted. Perhaps you have a background in a particular faith tradition, or no faith at all. But if you haven’t questioned what that means to you, or how that shapes who you are, now is a great time to reflect on that and do your own detective work. There’s nothing to lose from keeping an open mind, and if there really is a God who created you, then there’s everything to gain in your search for identity.
Interested in more content from scientists? Read this article by MIT professor, Ian Hutchinson: “Can a scientist believe in the resurrection? Three hypotheses…“
** Addendum to Veritas article
In this article, I stated in the first paragraph that referring to non-gene-coding DNA as “junk” is a ‘mistake.’ I believe it is important to explain this further in order to avoid any misconception of my original intent. Specifically, it is essential to clarify that by this I do not mean that the genome lacks any non-functional DNA. For a more detailed elucidation, it may help to start with a very brief history of the term “junk DNA.”
In 1972, well before the human genome project, Dr. Susumu Ohno predicted astutely that the bulk (>90%) of the human genome is comprised of genetic material that does not code for genes (Ohno, 1972). He reasoned that the non-gene-coding sequences arose in large part due to duplication of genes during evolution, and that these duplicated copies accumulated mutations, lost their original functions, and now serve primarily as “filler space” between the functional genes. He argued that while some of these duplicated gene copies (now generally referred to as ‘pseudogenes’) could in theory evolve new functions, most would likely decay at a neutral rate and remain as degenerate sequences: “failures of nature’s past experiments.” It was in reference to these regions that he coined the term “junk DNA.”
When the human genome project was completed, Dr. Ohno’s central claim was validated – that the bulk of the genome does not code for genes (Lander et al., 2001, Nature). But, importantly, it became clearer than ever before that while pseudogenes are indeed prevalent, the vast majority of Dr. Ohno’s “filler space” is actually comprised of repetitive DNA sequences (or ‘repeats’), which were predicted in 1980 (Orgel and Crick, 1980; Doolittle and Sapienza, 1980), as well as other large stretches of DNA with no known functions. By the early 2000s, the term “junk” had been somewhat organically expanded by some in the scientific community to include all such non-gene-coding DNA (not just the pseudogenes), which was incorrectly perceived by many to be largely inactive. Over time, in some scientific circles and even in everyday parlance, “junk” came to be used rather loosely to refer to any DNA lacking biochemical activity and/or function (though this was not quite the original intent).
It is the broad application of this sense of the word “junk” to non-gene-coding DNA that I am referring to as a ‘mistake.’ It likely would have been no surprise to Dr. Ohno, or indeed to most pre-genome era geneticists, that some portions of what had come to be known as “junk DNA” could function as gene “rheostats”, which I described in my article (McClintock, B., 1956; Britten and Davidson, 1969). But where the post-genome era has been most illuminating is in the sheer abundance and diversity of these “rheostats,” and in the newly evolved complex functions of pseudogenes (e.g., Tam et al., 2008, Cell; Karreth et al., 2015, Cell) and even some types of ‘repeats’ (e.g., Chuong et al., 2013, Nature Genetics; Wang et al., 2014, Nature). My intention in using the word ‘mistake’ was to caution against the persisting notion among some that the vast majority of non-gene-coding sequence has little-to-no biochemical activity or function (since this is how “junk” has come to be understood in some scientific and non-scientific circles). On the other hand, it is equally important to be clear that this caution does not imply that all non-gene-coding DNA is functional or useful to the organism. Indeed, I believe there is at this snapshot in evolutionary time some considerable “junk” in our DNA, with no current function, only a small fraction of which will likely evolve new functions in the future.
On this issue, as is usually the case in science, I believe it is best to avoid dogmatic or extreme views. Also, it would seem that it is perhaps of benefit to altogether avoid terms such as “junk DNA,” since it no longer has a singular meaning in the scientific community. Indeed, as our knowledge has advanced, it is a credit to our field and our enhanced understanding of the human genome that no single term can capture the heterogeneity and nuances of non-gene-coding DNA.
For those who are interested in more about “junk DNA” I encourage you to check out the following article: http://www.sciencedirect.com/science/article/pii/S0960982212011542.