In a groundbreaking study, Johns Hopkins University researchers followed nearly 800 Baltimore schoolchildren for a quarter of a century, and discovered that their fates were substantially determined by the family they were born into.

"A family's resources and the doors they open cast a long shadow over children's life trajectories," Johns Hopkins sociologist Karl Alexander says in a forthcoming book, The Long Shadow: Family Background, Disadvantaged Urban Youth, and the Transition to Adulthood. "This view is at odds with the popular ethos that we are makers of our own fortune."

Alexander, who joined Johns Hopkins in 1972 and retires this summer, spent nearly his entire career on the study, along with fellow researchers and co-authors Doris Entwisle and Linda Olson. Together they tracked 790 Baltimore children from 1982, the year they entered first grade, until they turned 28 or 29 years old, focusing in particular on those who started the journey in the most disadvantaged settings.

Through repeated interviews with the children and their parents and teachers, the research team observed the group as its members made their way through elementary, middle, and high school; joined the work force; and started families. The book, Alexander's fourth and final one culled from the project's data, details how the children's first years of life ultimately colored their success as adults.

The project was supposed to last only three years. Calling it the "beginning school study," the researchers had hoped to better understand how early home life helped some children successfully acclimate to first grade. But along the way Alexander and his team realized they had the foundation for something bigger—to watch the children's life trajectories unfold. And in most cases, they unfolded much as their parents' had.

At nearly 30 years old, almost half the sample found themselves at the same socio-economic status as their parents. The poor stayed poor; those better off remained better off.

Only 33 children moved from birth families in the low-income bracket to the high-income bracket as young adults; if family had no bearing on children's mobility prospects, almost 70 would be expected. And of those who started out well off, only 19 dropped to the low-income bracket, a fourth of the number expected.

"The implication is where you start in life is where you end up in life," Alexander said. "It's very sobering to see how this all unfolds."

Among the most striking findings: