Stephen Quake

Stephen Quake has the full lips and startling blue eyes of a cherub in a Renaissance painting, and the only sign that he is old enough to teach at a top academic institution is his corona of thinning curls. Wearing an olive-green golf shirt, loosely fitting khaki pants and sandals--the equivalent of formal attire among Caltech's lab rats--he ushers his visitor into an office where papers are stacked precariously high.

Stephen Quake has the full lips and startling blue eyes of a cherub in a Renaissance painting, and the only sign that he is old enough to teach at a top academic institution is his corona of thinning curls. Wearing an olive-green golf shirt, loosely fitting khaki pants and sandals--the equivalent of formal attire among Caltech's lab rats--he ushers his visitor into an office where papers are stacked precariously high.

Women may soon be able to find out very early in their pregnancies whether they are carrying a fetus with Down syndrome by offering a simple blood sample. The safe, noninvasive test would pose fewer risks to the mother and fetus than amniocentesis or chorionic villus sampling (CVS), the two tests currently used for prenatal diagnosis. It would also give women more time to decide what to do if a diagnosis of Down syndrome is made. Researchers from the Chinese University of Hong Kong have been working on the DNA-based test for a decade.

How long will it be before prenatal care involves sequencing the genome of a fetus to detect genetic disorders before birth? Several recent reports have shown it can be done, based on the tiny bits of DNA that float around in the mother-to-be's blood plasma during pregnancy. Another such study came out this week in the journal Nature -- with some important advances. In the past, fetal-genome analyses have involved getting samples of DNA from three places: the woman's blood cells (to identify her genome)