This week I've been thinking about babies. Healthy ones. Perfect ones. As you may have read last week, my colleague Antonio Regalado came face to face with a marketing campaign in the New York subway asking people tohave your best baby." The company behind that campaign, Nucleus Genomics, says it offers customers a way to...

This is today's edition ofThe Download,our weekday newsletter that provides a daily dose of what's going on in the world of technology. Expanded carrier screening: Is it worth it? Carrier screening tests would-be parents for hidden genetic mutations that might affect their children. It initially involved testing for specific genes in at-risk populations. Expanded carrier...