The head of the Health Ministry’s community genetics department, Prof. Joel Zlotogora, has requested that the public health basket committee recommends a blood test for pregnant women at high risk for having a fetus with Down Syndrome and certain other genetic disorders, The Jerusalem Post learned on Sunday.
Non-invasive prenatal diagnosis tests, which are made by five companies around the world, can differentiate between certain genetic data in the mother from that in her fetus (if she has only one embryo and did not receive a donated ovum). The blood sample is flown abroad for processing, mostly by US companies, and the results returned within a week to 10 days, informing the woman and her doctor on whether she is very unlikely to have a defective fetus or if it us at significant risk of such syndromes.
If the results show the fetus to be at a very low risk, the need for amniocentesis -- inserting a needing to remove a small amount of amniotic fluid from her uterus -- or other invasive sampling is unnecessary. This will thus save money for the health system. In addition, amniocentesis presents a small risk of spontaneous miscarriage.
If there is high risk, invasive testing can be carried out, and the couple could decide to abort the defective fetus if they wish. Zlotogora told the Post
that the technology -- first described in 1997 by Hong Kong scientist Dr. Dennis Lo -- is revolutionary. He recommended to the basket committee, which will meet in the fall for recommending expansion of the 2015 basket, that instead of giving free amniocentesis to any woman over 35, the eligibility for free blood tests should be determined by high risk (about five percent) and not by age.
The new blood tests, using various technologies, cost NIS 4,000 to NIS 6,000 in Israel. The existing foreign companies are called Natera, BGI, Ariosta, Sequenon and Verinata. However, if the Health Ministry agrees to adding the new technology, the cost of the test is sure to drop, and competition among the five companies is also certain to drive down prices.
The blood sample can be taken from a woman’s arm by any gynecologist, and the tests are carried out at the family’s expense. But Zlotogora said the new technology is revolutionary and could save the health system money. A few thousand Israelis have already paid for and undergone the test privately. It is said that amniocentesis is less common in the US because normal fetuses have been identified, making invasive tests unnecessary.
Among the defects picked up by the tests are Trisomy 21 (Down syndrome, caused by an extra copy of chromosome 21 and causing intellectual disability); Trisomy 18 (Edwards syndrome, caused by an extra copy of chromosome 18, causing severe intellectual disability and birth defects of various organs, with victims usually dying before their first birthday); Trisomy 13 (Patau syndrome, caused by an extra copy of chromosome 13 and causes severe intellectual disability and many serious birth defects, and its victims also die very before age one); Monosomy X (also called Turner syndrome, caused by a missing X chromosome, affecting only girls and causing physical defects, infertility and other problems; Triploidy (caused by having an extra set of 23 chromosomes and connected to severe birth defects).
Another congenital problems that can be detected by the blood test is Klinefelter syndrome (caused by an extra copy of the X chromosome, affecting only boys and causing learning disabilities and usually infertility). A vanishing twin, in which one of the fetuses of a multiple pregnancy dies in the womb, can also be detected by the test.
A full feature on the new blood tests will appear on the Health Page on Sunday, June 22.