1.   A thorough interview revealed no symptoms suggestive of inflammatory bowel disease in the healthy twins.

2.   The monozygotic twin material consisted of both concordant and discordant twin pairs, and some unpaired healthy twins.

3.   Both decided to have selective fetal reduction and each delivered healthy twins.

4.   Calvert said Sonny and Shadow are the first pair of healthy twins he has seen.

5.   Disease-fighting cells were removed from the healthy twin, retooled in the laboratory, then injected into the infected twin.

6.   The following December brought Teun and Koen, two healthy twin baby boys.

7.   But trying to abort just one fetus is too dangerous for the mother and the healthy twin.

8.   The research team last year cloned healthy twin calves at their facilities as part of the program.