Yang Wanli

China Daily (Latin America Weekly) - - China -

Non­in­va­sive pre­na­tal test­ing, which can de­tect Down syn­drome and other chro­mo­so­mal con­di­tions by check­ing a sam­ple of the mother’s blood, has been used in West­ern coun­tries for many years with­out con­tro­versy.

In China, NIPT, as it is known, was pi­loted in 2015, and of­fi­cial per­mis­sion for its clin­i­cal use na­tion­wide was granted the fol­low­ing year. Now, though, the test is fac­ing a cri­sis of trust.

In July, an 8-month-old boy from Hu­nan prov­ince was di­ag­nosed with men­tal dis­abil­i­ties and phys­i­cal de­for­mi­ties, de­spite hav­ing been as­sessed as low risk after his mother had an NIPT test dur­ing preg­nancy.

Although it was later proved that the test could not have de­tected the boy’s prob­lems, the case trig­gered pub­lic con­cern about the ac­cu­racy of NIPT after dozens of women were re­ported to have given birth to ba­bies with Down syn­drome after re­ceiv­ing “false-neg­a­tive” re­sults.

Con­trib­u­tory fac­tors

Ac­cord­ing to the most re­cent in­for­ma­tion avail­able — a re­port by the Na­tional Health and Fam­ily Plan­ning Com­mis­sion — the rate of birth de­fects na­tion­wide was 5.6 per­cent in 2012, mean­ing about 900,000 ba­bies were born with de­fects.

More­over, one in 10 fam­i­lies in China in­cluded a child with a dis­abil­ity, ac­cord­ing to the re­port.

“In ad­di­tion to fac­tors such as en­vi­ron­men­tal pol­lu­tion, ex­po­sure to ra­di­a­tion, or un­healthy life­styles, ge­netic prob­lems are among the most com­mon causes of a large num­ber of birth de­fects such as Down syn­drome, which re­tards phys­i­cal and men­tal devel­op­ment,” said Duan Tao, direc­tor of the Shang­hai Pre­na­tal Di­ag­nos­tic Cen­ter.

Duan said ge­netic dis­or­ders can be screened and di­ag­nosed pre­na­tally via ul­tra­sound ex­am­i­na­tion, con­ven­tional blood tests that mea­sure the lev­els of two spe­cific hor­mones and two pro­teins in the mother’s blood with an ac­cu­racy rate of about 60 to 70 per­cent, and NIPT, which has an ac­cu­racy rate of 99.3 to 99.5 per­cent.

NIPT de­tects chro­mo­so­mal dis­or­ders by an­a­lyz­ing a minute amount of pla­cen­tal DNA in the mother’s blood, ac­cord­ing to Zhou Daix­ing, CEO of Berry Ge­nomics, one of China’s largest next-gen­er­a­tion se­quenc­ing tech­nol­ogy com­pa­nies.

In the past seven years, the com­pany has pro­vided NIPT ser­vices to about 2.8 mil­lion women. It claims de­tec­tion sen­si­tiv­ity of 99.5 per­cent, based on clin­i­cal fol­low-ups of more than 1 mil­lion sam­ples.

Zhou said NIPT cov­ers three ma­jor chro­mo­so­mal dis­or­ders: Down syn­drome; Tri­somy 13 and Tri­somy 18 (which cause se­vere birth de­fects and ham­per devel­op­ment); and ir­reg­u­lar­i­ties in the num­ber of sex chro­mo­somes, which can lead to con­di­tions such as Turner or

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