From a vial of mom’s blood, a fetus’s entire genome

NEW YORK, (Reuters) – The days of pregnant women having a 3-inch-long (8-centimetre-long) hollow needle jabbed into their abdomens may be numbered.

For the second time in a month, scientists have announced that a simple blood test, rather than more invasive tests such as amniocentesis, can determine a fetus’s genetic make-up, identifying mutations causing any of about 3,000 inherited disorders that arise from a glitch in a single gene, such as cystic fibrosis. Unlike a procedure unveiled last month, the one announced yesterday in the journal Nature can be done without knowing who the father is, much less obtaining a sample of his DNA. Since paternity is unknown or incorrect in an estimated 3 to 10 percent of births in the United States, the father-free method promises to make fetal DNA sequencing possible in every pregnancy, if hurdles including cost and accuracy are overcome.