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Editor's note: Francis S. Collins, M.D., Ph.D., is the director of the Human Genome Project. His most recent book is "The Language of God: A Scientist Presents Evidence for Belief."

ROCKVILLE, Maryland (CNN) -- I am a scientist and a believer, and I find no conflict between those world views.

As the director of the Human Genome Project, I have led a consortium of scientists to read out the 3.1 billion letters of the human genome, our own DNA instruction book. As a believer, I see DNA, the information molecule of all living things, as God's language, and the elegance and complexity of our own bodies and the rest of nature as a reflection of God's plan.

I did not always embrace these perspectives. As a graduate student in physical chemistry in the 1970s, I was an atheist, finding no reason to postulate the existence of any truths outside of mathematics, physics and chemistry. But then I went to medical school, and encountered life and death issues at the bedsides of my patients. Challenged by one of those patients, who asked "What do you believe, doctor?", I began searching for answers.

I had to admit that the science I loved so much was powerless to answer questions such as "What is the meaning of life?" "Why am I here?" "Why does mathematics work, anyway?" "If the universe had a beginning, who created it?" "Why are the physical constants in the universe so finely tuned to allow the possibility of complex life forms?" "Why do humans have a moral sense?" "What happens after we die?" (Watch Francis Collins discuss how he came to believe in God )

I had always assumed that faith was based on purely emotional and irrational arguments, and was astounded to discover, initially in the writings of the Oxford scholar C.S. Lewis and subsequently from many other sources, that one could build a very strong case for the plausibility of the existence of God on purely rational grounds. My earlier atheist's assertion that "I know there is no God" emerged as the least defensible. As the British writer G.K. Chesterton famously remarked, "Atheism is the most daring of all dogmas, for it is the assertion of a universal negative."

But reason alone cannot prove the existence of God. Faith is reason plus revelation, and the revelation part requires one to think with the spirit as well as with the mind. You have to hear the music, not just read the notes on the page. Ultimately, a leap of faith is required.

For me, that leap came in my 27th year, after a search to learn more about God's character led me to the person of Jesus Christ. Here was a person with remarkably strong historical evidence of his life, who made astounding statements about loving your neighbor, and whose claims about being God's son seemed to demand a decision about whether he was deluded or the real thing. After resisting for nearly two years, I found it impossible to go on living in such a state of uncertainty, and I became a follower of Jesus.

So, some have asked, doesn't your brain explode? Can you both pursue an understanding of how life works using the tools of genetics and molecular biology, and worship a creator God? Aren't evolution and faith in God incompatible? Can a scientist believe in miracles like the resurrection?

Actually, I find no conflict here, and neither apparently do the 40 percent of working scientists who claim to be believers. Yes, evolution by descent from a common ancestor is clearly true. If there was any lingering doubt about the evidence from the fossil record, the study of DNA provides the strongest possible proof of our relatedness to all other living things.

But why couldn't this be God's plan for creation? True, this is incompatible with an ultra-literal interpretation of Genesis, but long before Darwin, there were many thoughtful interpreters like St. Augustine, who found it impossible to be exactly sure what the meaning of that amazing creation story was supposed to be. So attaching oneself to such literal interpretations in the face of compelling scientific evidence pointing to the ancient age of Earth and the relatedness of living things by evolution seems neither wise nor necessary for the believer.

I have found there is a wonderful harmony in the complementary truths of science and faith. The God of the Bible is also the God of the genome. God can be found in the cathedral or in the laboratory. By investigating God's majestic and awesome creation, science can actually be a means of worship.

What is your take on this commentary? E-mail us

The opinions expressed in this commentary are those of the writer. This is part of an occasional series of commentaries on CNN.com that offers a broad range of perspectives, thoughts and points of view.

Your responses

CNN.com asked readers for their thoughts on this commentary. We received a lot of excellent responses. Below you will find a small selection of those e-mails, some of which have been edited for length and spelling.

Lorri Carlson, Prescott, Arizona

I am greatly encouraged to read about Dr. Francis Collins' intellectual and spiritual perspective. It is positively refreshing. A thinking person who recognizes the complementary relationship of faith in Jesus Christ and science! Thank you so much for making this article available.

Alan Goldstein, Powder Springs, Georgia

As is typical of believers, Collins was looking for answers, and when he didn't find them (or more likely didn't care for the answers he found), he turned to superstition. For example, what is the meaning of life? Science would say "Life has no meaning, other than the meaning we give to it." I think this is a wonderful answer, and immensely preferable to, life exists because god was bored. And that our sole purpose for existence is to please god enough, so that we may enter heaven and sing his praises for all eternity.

Hyukwoo Shin, Del Mar, California

It is no surprise to me that an accomplished scientist like Dr. Collins is a faithful believer because he asked himself the right questions. I see so many times atheists in science asking the wrong questions: "Can you prove that the bible is true or that God does exist?" The right questions are pointed out in this article: "What is the meaning of life?" "Why am I here?"

James Lampert, Fountain Valley, California

The best case of all for the existence of a supreme being is in the very laws of physics: the fact that physics HAS laws, and that those laws are knowable, internally consistent, and elegant.

Barbara Liang, Appleton, Wisconsin

Dr. Collins stated that in his late 20s he made a leap of faith and embraced the Christian teachings because he could no longer live with "uncertainties." An emotional quest for certainty and tranquility, no matter how beneficial to the individual, does not a factual system make. I am glad that Dr. Collins has the comfort of his beliefs, but his reasoning does not sound very scientific.

James Hastings, Franklin, Pennsylvania

Thanks for publishing this point of view. I don't agree with the author, but it was refreshing to read commentary that was different from the conventional wisdom published ad nauseum. Maybe this sort of writing should appear more often than "occasionally."

John Borland, Waukegan, Illinois

I am with Dr. Collins until he broaches the subject of Jesus. He poses questions about whether it is possible to reconcile Jesus' divinity with science, but he avoids answering them by devoting the remainder of the piece to evolution and the age of the earth. It seems to me that believing in Jesus, or any other divine prophet, requires an egocentric view of creation that goes far above and beyond Dr. Collins' argument for belief in God. To casually insert a reference to Jesus in this piece without addressing that issue seems to me to be an obvious attempt to blur the distinction. It makes the piece seem more like an advertisement for Christianity than a thoughtful discussion of spirituality.

Suzanne Spinelli, Middlebury, Connecticut

I agree with the scientist in the report, however, why is it only Judeo/Christian creation myth that can be 'real.' There are many different creation myths from the past until the present. I think it is offensive to negate all those other myths for the "one true 'real'" myth (depending on one's point of view). After all, who is to say which one is right? Could it be that they are all right in their own way?

Mara Alexander, Alexandria, Virginia

With a Ph.D. in the social sciences, I'd find it more surprising that scientists don't believe in a god or organizing principle of some sort. What we pursue is "truth," with the underlying belief that there is order in the universe if only we can discover it. I don't know that I especially believe in a berobed deity sitting up in Heaven, or in a literal version of the Bible, but I certainly do believe in a higher power of some sort.