Chapter Excerpt

Moses called the blistering sands of ancient Canaan "a great and terrible wilderness." On a cloudless day, on a plane at 10,000 feet, the allure is immediately apparent. The vast plateau of the Negev, the northern Sinai in Egypt, and Jordan's southern desert rarely looks like the sweeping, endless dunes of popular imagination. More commonly, it resembles a visually dissonant landscape of dusty hills lined with scarps and dotted with scraggly bushes and rocks. It is untamed beauty, with barren stretches interrupted only by Bedouin tent villages and archaeological oases that seem to come and go with the wind.

My throat clogged in the heat of the afternoon desert air as I walked off the small Arkia jet and onto the melting tarmac in Eilat, Israel's Red Sea beach town at the tip of the Negev Desert. Set in a stunning location along the Gulf of Aqaba, which divides the Sinai from the Arabian Peninsula, this palm-fringed city had thrived by attracting sun-worshippers from France, Italy, and Scandinavia. Scuba divers still explore the deep aqua waters, ablaze with coral reefs, that wash on its shores. But like the rest of Israel, this oncegleaming resort is struggling, another casualty of the tension that engulfs the Middle East. My beachfront hotel stood empty, save for a large group of unruly students from suburban Tel Aviv vacationing on the cheap.

Israel is central to Western culture and religion despite-or perhaps because of-its challenging topography, where the identity of the Israelites was forged. This scruffy region is a "land flowing with milk and honey," as God promised to Moses as he began his desert sojourn in Canaan, but mostly in the spiritual sense, for life here has always been a test. The desert did not share in the prosperity spilled along the fertile banks of the bountiful rivers that spurred the rise of two other centers of ancient civilization, along the Nile in Egypt and the Tigris and Euphrates in Mesopotamia. The "mighty" Jordan River that divides Israel and Jordan-ancient Judea* and Samaria to the west and Edom to the east-was always richer in folklore than volume. Today in many spots it is little more than a trickle.

My visit to Israel was a deeply personal journey, spurred by the tragedy that DNA has visited upon my family. Although raised as a Reform Jew, dutifully bar mitzvahed and confirmed, and even though I had majored in religion and philosophy in college, I had long since lost my faith. The final break came in my teen years, in 1970, when my mother died of ovarian cancer, an unrelenting disease that spread to her brain. She had fought courageously for years, undergoing chemotherapy that left her bloated and caused her hair to drop out. My father, a dentist turned drug sleuth, scoured the world for potential treatments, eventually finding a promising new drug in Israel, unapproved at that time in the United States, that he smuggled home in his luggage in a desperate attempt to keep her with us a little longer. Her doomed struggle has left me with a haunting memory. Although I was only fifteen when she began the secret therapy, she asked me to give her the daily injection that we all viewed as her long-shot lifeline; she believed I would administer the shot more gently than my dad. I watched her every day, too closely, as the cancer spread.

My mother was neither the first nor the last person in my family to suffer from cancer. Two years before, my grandmother, living in our home, passed away from breast cancer. It also took my mother's younger sister, in her thirties. Because science was not yet able to explain the origins of this type of cancer, our family believed the three deaths were tragically unfortunate coincidences. As we were later to learn, my mother and her family were victims not of bad luck but of a bad gene.

A few years ago, I received a horrific call from my older sister, Judy. She too had been diagnosed with breast cancer, a rapidly spreading kind similar to the version that had savaged our aunt, grandmother, and mother. Thirty years after my mother died, the science of genetics had come a long way. Judy underwent a genetic test that revealed that her cancer was almost certainly caused by a mutation on one of her genes. Identified just over a decade ago, it was dubbed the BRCA2, or BReast CAncer 2 mutation 6174delT, one of three breast cancer mutations that are particularly common among Jews. My family tree disappears into the nineteenth-century eastern European diaspora, so it's difficult to trace the history of this wayward gene in my maternal line. The only thing that can be said with near certainty is that it's a tragic marker of our family's Jewish ancestry.

It's estimated that one in forty-three Jews (about 2.5 percent), women and men, carry one of these three gene faults. Being a carrier doesn't mean you have or will definitely get breast or ovarian cancer. It does mean that cancer is much more likely to develop because your cells are one critical step further along the road to becoming cancerous than they would be if you didn't carry the mutation. While the general population faces a 10 percent risk of developing breast cancer, the risk for women with one of these mutations may rise during their lifetime to more than 80 percent, even for women with no family history of the disorder. For many female carriers, it used to be an almost certain death sentence.

Defying the grim odds, Judy fought the disease to a standstill, showing remarkable courage; tapping into the support of her husband, family, and friends; and seeking the advice of medical experts and geneticists who were not available to my mother decades ago. She's now healthy and disease-free. When she was diagnosed, she had urged me and Joan, the middle child in our family, to get tested. Like many people who learn they might be carrying a genetic defect, Joan didn't want the burden of knowing if she was a carrier. She had no daughter to whom she could have passed along the mutation, so she declined to be tested.

I chose differently. By pure coincidence, I had written about the DNA revolution in previous books on genetic engineering in agriculture and on the role genes play in influencing which races do best in which sports.* But now genetics was a family and deeply personal concern. I have a young daughter who might have inherited the disease mutation from me, so I decided to be tested.

The news was not good. I too carry the cancer mutation. Its effects on men include a slight risk of breast cancer-yes, I now get my breasts squeezed and poked each year-and slightly increased risks of pancreatic cancer, prostate cancer, and melanoma of the eye. Although I tested positive, I was not allowed to go the next step and find out whether my daughter had inherited this potentially killer gene from me. Myriad Genetics, which isolated the BRCA mutations, does not allow its test to be administered to minors. It holds that a mutation in someone so young would not yet be showing its effects, and as there are no preventive measures, a positive test would needlessly frighten. The decision was made for me. We would have to wait until she was eighteen, and then it would be her choice whether to proceed with the test.

We've all heard the phrase "We are, regardless of race, 99.9 percent the same." Yet here was a pinpoint of DNA that suggests that maybe human population groups are not quite so alike as the common wisdom holds. However slight the genetic differences (and geneticists now believe that they are far greater than the 0.1 percent that previously had been estimated), they are defining. They contain the map of my family tree back to the first modern humans. They catalog my extended family's vulnerability to many diseases. And they mark me indelibly as a Jew. Almost every minority group, at one time or another, has faced being branded based on a superficial understanding of how genes work. The inclination by politicians, educators, and even some scientists to highlight the threads that bind together the world's diverse populations and underplay our separateness is certainly understandable. But it's also misleading. DNA ensures that we differ not only as individuals but as groups.

The modern age of genetics is symbolized by the famous image of the twisted ladder of chemical crossbars of deoxyribonucleic acid. It took years after the basic structure of DNA was identified before scientists could draw even a rough outline of the script that nature took billions of years to compose. "Today we are learning the language in which God created life," noted President Bill Clinton in June 2000, invoking religious metaphors in announcing the first working draft of the human genome. Francis Collins, director of the National Human Genome Research Institute, who was an atheist and is now a practicing Christian, drew an even more direct religious reference at that news conference. "We have caught the first glimpses of our instruction book, previously known only to God," he said.

This book offers a story of faith and science. I embarked on this journey as a skeptic by nature and profession, and from my vantage point as a "High Holy Day Jew"-what many Orthodox believers, without humor, call a "gentile." But this book suggests that religious identity extends beyond beliefs. Our genes carry meaning. This ancient script now being deciphered is literally lifting the curtain on God or Nature's plan. While often at odds, religion and science are spinning an interlaced narrative of identity. It's a story that begins in the ancient Middle East.

ISRAELITE GENES

What can DNA tell us about the shared legacy of the Israelites? Christians, Muslims, and Jews have always recognized a common spiritual heritage that originates with "Abraham, our father"- the progenitor of 2 billion Christians, 1.3 billion Muslims, and 13 million Jews. "I will establish My covenant between Me and you," God announces in Genesis to Abraham, promising that his descendants will be "as numerous as the stars of the heaven and the sands on the seashore. . . . I assign the land you sojourn in to you and your offspring to come, all the land of Canaan, as an everlasting holding. I will be their God." Abraham and his descendants will forever be unique, their future in the Promised Land irrevocably bound to the grace and favor of God.

What of this story is true? What evidence exists to support the central narratives of the Hebrew Bible-the birth of the Israelite people under Abraham, the Exodus, the golden age of the Davidic Empire, and the story of the Lost Tribes, among others? After all, no existing records other than the Hebrew Bible refer to Abraham, a sizable Israelite presence in Egypt, or even the Exodus.

Many early religious leaders, Jewish and Christian, including Saint Augustine in De Genesi ad litteram, written near the end of the fourth century ce, professed that aspects of the Hebrew Bible should not be taken at face value. But Christian orthodoxy ultimately overwhelmed theological rationalism. From the fall of the Roman Empire until the mid-nineteenth century, when Charles Darwin proposed a heretical naturalistic explanation of human origins, a literal interpretation prevailed. Over the past century, skeptics and scholars known as biblical minimalists have chipped away at many key stories. Nature's cemeteries have yielded skeletal remains, coins, pottery shards, and flint tools with exotic engravings that have enriched and often rewritten classical narratives. But like the ancient biblical accounts, the bones and stones of history have left us with chapters abbreviated and characters missing. The metamorphosis of the scattered Israelite tribes into a proud and irascible people has remained only dimly visible.

Questions remain. Were Abraham, Moses, and David real people? What happened to the Twelve Tribes? Can some modern Jews actually trace their ancestry as Jewish priests to Aaron? Did descendants of King Solomon and the queen of Sheba build the fabulous stone palace in the heart of Africa known as the Great Zimbabwe? Is Britain or the United States the "New Jerusalem" foretold in the Bible? Are the American Indians descendants of Abraham, as some Mormons believe? What happened to the Jews who converted to Christianity during the Spanish Inquisition? Who are the real "chosen people"-Arabs or Jews? Are the majority of today's Jews descendants of non-Jewish Eurasians and Europeans? If the maternal lineage of many modern Jews begins with gentiles, as history and DNA suggest, and they did not formally convert to Judaism, what determines "Jewishness"? If blood ties were paramount to our Israelite forebears, then our genes, protected against the ravages of time and passed on from generation to generation, must carry some record of the Israelites, the origins of Christianity and Islam, and the long and contentious travail of the Jews.

DNA has for good reason been described as "the book of life." The cells in the human body make up a vast library that carries the story of all life on earth, which began with our protozoan ancestors, the organisms that lived some 4 billion years ago. Each of those 100 trillion cells is a microscopic, soupy, fluid-filled bag with a tiny blob called a nucleus floating inside. That's where our life's book is archived. Each nucleus contains forty-six chromosomes - two pairs of twenty-three spiral DNA strands. They hold the code for how each cell should work and therefore how traits-from the shape of our nose to our temperament-shall be expressed.

The portions of the DNA that contain the recipe of life are known as genes. The "sentences" for these instructions are proteins, which are made up of amino acids, or "words," each of which consists of "letters"-nucleotides. There are enough letters in the human genome-more than 6 billion nucleotides that make up 3 billion base pairs-to fill thousands of Bibles. This immense encyclopedia of evolution fits inside the nucleus of every cell. If stretched out, the DNA in each human chromosome would extend an inch or more, but it is compacted into a microscopic bolus of only 0.001 inch. Each cell has a full set of DNA instructions. So, for instance, a hair cell also has the genetic information on how to make teeth or eyes, but those sections of the DNA are shut down in that particular cell. It's why crime scene investigators can take a sample of DNA from any part of the body and get a distinct signature of that individual and how genetic identity seekers can map the story of our ancestral history back to biblical times. Using unique DNA markers, our female ancestral lineage can be traced through the energy center of cells, known as mitochondria. The narrative of the male line is embedded on the male sex chromosome, Y. Yet another set of ancestral stories emerges from the vast majority of genes, known as autosomes, found on the rest of the human genome.

What our DNA reveals is at once comforting and disquieting, for it confirms our common humanity and yet challenges deeply held beliefs of equality. We often hear talk in our cosmopolitan capitals that we live in a global village and a world melting pot, but our genes tell a more complex story of diversity and differences. Over many thousands of years, twigs off the human family tree-bands of extended relatives, clans, tribes, and what scientists call populations-migrated throughout the world. Although "the urge to merge with a splurge," as Cole Porter once put it, has inexorably erased many of the most visible signs of our ancestral roots, we are still a long way from shedding the heritage embedded in our genes.

The story contained in our DNA raises the taboo issues of race, disease, and intelligence. Genetic anthropology and genealogy are tightly bound to the worldwide effort to address many behavioral and medical problems, which is a key impetus behind the Human Genome Project. Genetic differences, and sometimes just one gene, can confer near-certain death sentences, while other people are mysteriously spared. There are thousands of genetic disorders, hundreds of which disproportionately affect one racial or ethnic group.

Although rare in blacks and Asians, cystic fibrosis is a common lethal genetic disease in those of northern European ancestry. Whites are more likely to get multiple sclerosis than all other population groups, while blacks and some Mediterranean populations are susceptible to sickle cell anemia. Some 2 million whites worldwide now carry copies of a mutant gene that makes them immune to human immunodeficiency virus (HIV) infection. Rare mutations may help insulate some southern Asians from severe acute respiratory syndrome (SARS). The presence of one gene is a potent risk factor of Alzheimer's for whites, but not for blacks. The variant of one gene may explain why black women have twice the risk of premature delivery than women of European ancestry. Those of African ancestry are more susceptible to heart disease and are 50 percent more likely than whites to die of colorectal cancer, even if they receive the same treatment. Irish and others of Celtic ancestry are disproportionately victimized by Dupuytren's disease, also known as claw hand. One mutation accounts for the sensitivity of the Japanese to alcohol, while another gene variant carried by at least a fifth of all Semites helps them break down liquor in the bloodstream, protecting them against alcoholism.

Although geneticists generally avoid using the term "racial" to characterize differences that show up more in one population than others, ancestry matters. Because modern humans move around and fool around far more expeditiously than their ancient ancestors, modern "races" and ethnic groups are fuzzy at the edges and overlapping. As a rule, the more historically isolated a population- because of geographical or cultural barriers-the more distinct its genetic makeup. Tantalizing clues about the origin of diseases have prompted researchers to focus on a number of geographically circumscribed groups; Icelanders, Finns, indigenous Ainu of Japan, American Indians, Costa Ricans, Maori of New Zealand, Sardinians, Basques, rural Chinese, and various West African tribes and their descendants are examples. Known as founder populations because they tend to preserve the genetic makeup of the founders, these groups have two key attributes: only a few thousand primary ancestors and little intermarriage in succeeding generations. Other genetic islands have been shaped by strong religious and cultural beliefs-Gypsies, the kindred clans of Mennonites and Amish, Hutterites, and Parsis. But no gene pool has been more crucial for DNA research and the quest to develop medical cures than the diaspora communities of the Jews.

Jews have unique advantages as candidates for genetic study. Since being expelled from biblical Palestine to the far corners of the globe, they have congregated in many tightly knit but intricately linked communities. For the most part, they were endogamous- they rarely married outside the religion, at least until the twentieth century. That fidelity has proved a gold mine for DNA researchers. "Jewish genetics," as it has been called, is at the center of a worldwide quest to solve the puzzle of disease and unlock the backstories of humanity. Archival vaults once thought buried in time are being pried open. Provocative answers to questions of ancestry and identity, once considered answerable by faith alone, might be found in our DNA. It's the genetic equivalent of history's Dead Sea Scrolls. Consider the story of Father William Sánchez.

Copyright © 2007 by Jon Entine, all rights reserved