Ming-Jie Yang1, Cheng-Hwai Tzeng, Jen-Yu Tseng, Ching-Ying Huang. 1. Department of Obstetrics and Gynecology, Taipei Veterans General Hospital, National Yang-Ming University School of Medicine, Taiwan, R.O.C. mjyang@vghtpe.gov.tw
Abstract
BACKGROUND: The aim of this preliminary study was to estimate the accuracy of the zygosity determination in twin pregnancies. METHODS: Seventy-three sets of twin pregnancies were enrolled in this study, including 48 sets of twins resulting from assisted reproductive techniques (ART) and 25 sets of spontaneously conceived twins. Determination of zygosity was made by PCR-amplified short tandem repeat (STR) analysis with a commercially available panel, comprising 15 autosomal, codominant, unlinked loci and the gender-determining marker, amelogenin. Monozygotic (MZ) twins were determined when all these unlinked loci and the gender-determining marker were identical. Chorionicity and placenta were examined after delivery of the newborns to check their relationships to the twin zygosities. RESULTS: Three of 48 (6.25%) sets of twins produced by ART and 18 of 25 (72%) sets of spontaneously conceived twins were MZ. Monozygosity could be evaluated based on 'like sex' in spontaneously conceived twins, because they had a greater incidence of MZs than those produced by artificial reproductive techniques. The MZ prediction rate was 78.6%, and the overestimated rate was 21.4% if the monochorionic like-sexed twins (LST) had a grossly single placenta. The underestimated rate of MZs was 26.7% when the dichorionic LST had apparently separate placentas. CONCLUSION: With the DNA-based 15 STR analysis amplified in a multiplex PCR, the determination of the zygosity in multifetal pregnancies is not only cost and time saving but also yields greater sensitivity and precision than conventional methods.
BACKGROUND: The aim of this preliminary study was to estimate the accuracy of the zygosity determination in twin pregnancies. METHODS: Seventy-three sets of twin pregnancies were enrolled in this study, including 48 sets of twins resulting from assisted reproductive techniques (ART) and 25 sets of spontaneously conceived twins. Determination of zygosity was made by PCR-amplified short tandem repeat (STR) analysis with a commercially available panel, comprising 15 autosomal, codominant, unlinked loci and the gender-determining marker, amelogenin. Monozygotic (MZ) twins were determined when all these unlinked loci and the gender-determining marker were identical. Chorionicity and placenta were examined after delivery of the newborns to check their relationships to the twin zygosities. RESULTS: Three of 48 (6.25%) sets of twins produced by ART and 18 of 25 (72%) sets of spontaneously conceived twins were MZ. Monozygosity could be evaluated based on 'like sex' in spontaneously conceived twins, because they had a greater incidence of MZs than those produced by artificial reproductive techniques. The MZ prediction rate was 78.6%, and the overestimated rate was 21.4% if the monochorionic like-sexed twins (LST) had a grossly single placenta. The underestimated rate of MZs was 26.7% when the dichorionic LST had apparently separate placentas. CONCLUSION: With the DNA-based 15 STR analysis amplified in a multiplex PCR, the determination of the zygosity in multifetal pregnancies is not only cost and time saving but also yields greater sensitivity and precision than conventional methods.
Authors: Sun Ah Choi; Jung Min Ko; Choong Ho Shin; Sei Won Yang; Jin Sun Choi; Sun Kyung Oh Journal: Eur J Pediatr Date: 2013-04-05 Impact factor: 3.183
Authors: Meena S Ramchandani; Lichen Jing; Ronnie M Russell; Tran Tran; Kerry J Laing; Amalia S Magaret; Stacy Selke; Anqi Cheng; Meei-Li Huang; Hong Xie; Eric Strachan; Alex L Greninger; Pavitra Roychoudhury; Keith R Jerome; Anna Wald; David M Koelle Journal: J Infect Dis Date: 2019-03-15 Impact factor: 5.226