A man is phoned and is told his child is probably genetically insufficient. A blood test suggested the possibility of Down syndrome, and the doctor was recommending amniocentesis (amniocentesis n. (pl. -teses) sampling of amniotic fluid to detect foetal abnormality. But the odd question arises: Will we know too much? Fetal and embryonic genetic karyotypes may ultimately be as legible as a topographical map: Your son will be born healthy; he will be allergic to …showed first 75 words of 3223 total…

…showed last 75 words of 3223 total…than one species. But even if this doesn't happen, our thin metaphysical membrane of human solidarity might easily rupture under the strain. "The mass of mankind has not been born with saddles on their backs," Thomas Jefferson wrote two centuries ago, "nor a favored few booted and spurred, ready to ride them . . ." Who today can consider the momentum of genetic research and be confident that in another two centuries Jefferson's words will still hold true?