Prenatal diagnosis of single gene disorders and role of multidisciplinary cooperative mode

Objective To evaluate the trend in prenatal diagnosis of single gene disorders (SGD) and role of multidisciplinary cooperative mode. Methods In January 1, 2012, a multidisciplinary cooperative mode for SGD diagnosis was established in the Peking University First Hospital, involving Departments of Obstetrics, Pediatrics, Neurology, Dermatology and Central Laboratory. For each pregnant woman with a family history of SGD for prenatal diagnosis, propositus should be diagnosed in the relevant departments, and then further diagnosed, managed and followed up by the Obstetrics Department. Up to December 31, 2014, of 6 681 women for prenatal diagnosis, 279 women had a family history of SGD: 76 of them received chorionic villus sampling (CVS) at 11 – 14 gestational weeks, and 203 received amniocentesis (AC) at 16 – 22 gestational weeks. The trend in SGD diagnosis and the safety of CVS and AC were analyzed using Chi–square test. Results The proportion of SGD family history in AC group was 3.2% (203/6 355), which stayed stable with 2.3% (47/2 054) in 2012, 3.9% (78/2 023) in 2013 and 3.4% (78/2 278) in 2014, and there was no significant difference between 2013 and 2014 (χ2=0.571, P=0.463). In CVS group, the proportion of SGD family history was 23.3% (76/326), showing an increasing trend with 18.2% (8/44) in 2012, 17.6% (19/108) in 2013 and 28.2% (49/174) in 2014, and there were significant differences between 2013 and 2014 (χ2=4.067, P=0.046). The proportion of SGD family history in CVS group was higher than in AC group in year 2012, 2013 and 2014 (χ2=42.626, 44.531 and 201.400, all P=0.000). Among the 279 cases of SGD family history, no complications and adverse outcome were observed except an intra–uterine fetal death occurring 6 months after CVS in one woman, but 3 fetuses were found to have chromosome anomalies with one trisomy 18, one 45, X, and one mosaicism of 45,X/46,XY which was determined to be normal by AC. Conclusions SGD family history is one of the important indicators in prenatal diagnosis, and CVS is feasible for prenatal diagnosis of SGD family history as early as in the first trimester. Multidisciplinary cooperative mode is helpful in SGD family history diagnosis. Key words: Genetic diseases, inborn; Prenatal diagnosis; Chorionic villi sampling; Pregnancy trimester, first