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From DNA to People: A Molecular Primer

From DNA to People: A Molecular Primer

The Genetic Journey: Following DNA from Cell to Society

It is morning. You wake up, slurp some coffee and navigate your way to work. You say hello to people, and so begin your day. Unremarkable? Hardly.

By Brian W. Simpson

Consider the complex biological symphony that makes it all possible. Let's start with the 100 trillion cells in your body. In nearly every one is coiled more than six feet of DNA containing the collective evolutionary history of humanity, as well as the special recipe of 3.2 billion chemical "letters" that make up the unique you. Along the DNA sequence are your 30,000 or so genes. They help create proteins, the body's busy bees that hustle among and within cells doing everything from escorting oxygen about the body to topping your head with hair.

Next, consider how all of your cells arrange themselves into essential organ systems (your stomach, your brain, etc.) and preserve that most desired of biological states—the even keel of homeostasis. Add to this the fact that parasites, viruses and other interlopers constantly come calling, many with insidious intent. Such biological pathogens and chemical toxins can gum up the genetic works and cause mistakes and mutations. And the subtlest change in a gene may lead to disease.

Given such dizzying intricacy and innumerable moving parts, veteran researcher Sharon Krag says, "You can sit back and say, 'My God, I'm here, and most days I'm normal.' That's a miracle in itself."

But how does this quotidian miracle happen? We're at least somewhat familiar with the players: deoxyribonucleic acid, genes, chromosomes, cells, proteins and so on. We bandy about the terms with casual insouciance (and, for most of us, superficial knowledge), but how do they actually figure into human health? And more importantly, exactly why do things go wrong? Can a better understanding of genes help us foil cancer, discover the source of bipolar disorder, eradicate dengue or yellow fever, prevent Alzheimer's or improve children's nutrition in the developing world?

To glimpse how scientists at the Bloomberg School are seeking answers to these and other questions, join us on an incredible journey as we follow DNA—the thread of life—from its minute chemical bonds to its dramatic effects on the health of human populations.

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