Since 1950, dramatic advances in human genetics have occurred, racial disparities in infant mortality have widened, and the United States' international ranking in infant mortality has deteriorated. The quest for a "preterm birth gene" to explain racial differences is now under way. Scores of papers linking polymorphisms to preterm birth have appeared in the past few years. Is this strategy likely to reduce racial disparities? We reviewed broad epidemiological patterns that call this approach into question. Overall patterns of racial disparities in mortality and secular changes in rates of prematurity as well as birth-weight patterns in infants of African immigrant populations contradict the genetic theory of race and point toward social mechanisms. We postulate that a causal link to class disparities in health exists.