Matt and Andrea Thomas spotted each other walking across campus at Texas A&M University, struck up a conversation, and fell in love. They married after graduation and found jobs in Austin, Texas-Matt as an engineer and Andrea as a teacher. Having children seemed like the next step in their lives together.

President Bush met with U.S. vaccine developers on Oct. 7, not long after reading a gruesome history of the 1918 Spanish flu pandemic. The 500-plus page book by John M. Barry tells how 40 million of the world's youngest, healthiest people died horrifically, bleeding from their ears and noses and turning blue from lack of oxygen. The book also skewers military and government officials who ignored warnings about poor public health conditions in barracks and cities.

Professor Ian Wilmut of the University of Edinburgh envisions a world where sick people could draw new life from younger, healthier clones of themselves. Mr. Wilmut became famous for cloning Dolly the Sheep and is now one of the most prominent embryonic stem-cell and human-cloning researchers.

The days following Senate Majority Leader Bill Frist's speech supporting embryonic stem-cell research unfolded like a messy, public breakup. Pro-lifers crumpled into their chairs like scorned lovers to pound out angry notes to all their friends in the blogosphere. They called him a flip-flopper and pointed out all the times Mr. Frist had done them wrong. They reminded one another that he supported abortionist David Satcher's nomination as surgeon general.

For the past several months, Majority Leader Bill Frist had the job of overseeing in the U.S. Senate six proposals to escalate embryonic stem-cell research. In the Bush administration's eyes, Mr. Frist's job was simple: Stop all six and spare the president from having to veto a bill for the first time in his four-and-a-half years in office.

When a South Korean scientist took the lead in the stem-cell research race, U.S. lawmakers quickly moved to change the rules. Catching up with South Korea was so urgent that within days of Seoul's May 19 breakthrough announcement, Republicans and Democrats pulled pro-stem-cell legislation to the House floor. Lawmakers had expected a vote on the Stem Cell Research Enhancement Act, but not necessarily one that bypassed the committee where it had sat untouched for months.

LAWRENCE, Kan. - At the University of Kansas, Dr. Kathy Mitchell has two small labs that resemble high-school biology classrooms, just with more expensive equipment. In the smallest one, the size of a large supply closet, she pulls up a computer screen showing fluorescent dots in a sea of translucent green. She clicks her mouse, and the dots, which are stem cells, start to repair a gash in the green membrane, which is a layer of kidney cells.