Abstract：
OBJECTIVE: We present mosaic trisomy 16 at amniocentesis in a pregnancy associated with positive non-invasive prenatal testing (NIPT) for trisomy 16, placental trisomy 16, intrauterine growth restriction (IUGR), intrauterine fetal death (IUFD), cytogenetic discrepancy between cultured amniocytes and uncultured amniocytes and uncultured amniocytes, and prenatal progressive decrease of the aneuploid cell line.
METHODS: A 26-year-old, primigravid woman underwent amniocentesis at 17 weeks of gestation because of positive NIPT for trisomy 16 at 12 weeks of gestation. Amniocentesis revealed a karyotype of 47,XX,+16 [10]/46,XX[17], and simultaneous array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes revealed the result of arr (16) × 3 [0.43] consistent with 43% mosaicism for trisomy 16. She was referred for genetic counseling at 19 weeks of gestation, and a fetus with IUGR was noted to have a size equivalent to 16 weeks of gestation. At 23 weeks of gestation, the fetus manifested oligohydramnios, fetal cardiomegaly and severe IUGR (fetal size equivalent to 20 weeks of gestation). Repeat amniocentesis revealed a karyotype of 46,XX (20/20 colonies) in cultured amniocytes and mosaic trisomy 16 by aCGH in uncultured amniocytes. aCGH analysis on uncultured amniocytes revealed the result of arr 16p13.3q24.3 × 2.3, consistent with 30% (log2 ratio = 0.2) mosaicism for trisomy 16. Quantitative fluorescence polymerase chain reaction (QF-PCR) assays on the DNA extracted from parental bloods and uncultured amniocytes excluded uniparental disomy (UPD) 16. The parental karyotypes were normal. IUFD was noted at amniocentesis. The pregnancy was subsequently terminated, and a 288-g female fetus was delivered with no phenotypic abnormalities. The umbilical cord had a karyotype of 46,XX (40/40 cells), and the placenta had a karyotype of 47,XX,+16 (40/40 cells). QF-PCR assays of the placenta confirmed a maternal origin of trisomy 16.
CONCLUSIONS: Mosaic trisomy 16 at amniocentesis can be associated with positive NIPT for trisomy 16, placental trisomy 16, IUGR, IUFD, cytogenetic discrepancy between cultured amniocytes and uncultured amniocytes, and prenatal progressive decrease of the aneuploid cell line.
METHODS: A 26-year-old, primigravid woman underwent amniocentesis at 17 weeks of gestation because of positive NIPT for trisomy 16 at 12 weeks of gestation. Amniocentesis revealed a karyotype of 47,XX,+16 [10]/46,XX[17], and simultaneous array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes revealed the result of arr (16) × 3 [0.43] consistent with 43% mosaicism for trisomy 16. She was referred for genetic counseling at 19 weeks of gestation, and a fetus with IUGR was noted to have a size equivalent to 16 weeks of gestation. At 23 weeks of gestation, the fetus manifested oligohydramnios, fetal cardiomegaly and severe IUGR (fetal size equivalent to 20 weeks of gestation). Repeat amniocentesis revealed a karyotype of 46,XX (20/20 colonies) in cultured amniocytes and mosaic trisomy 16 by aCGH in uncultured amniocytes. aCGH analysis on uncultured amniocytes revealed the result of arr 16p13.3q24.3 × 2.3, consistent with 30% (log2 ratio = 0.2) mosaicism for trisomy 16. Quantitative fluorescence polymerase chain reaction (QF-PCR) assays on the DNA extracted from parental bloods and uncultured amniocytes excluded uniparental disomy (UPD) 16. The parental karyotypes were normal. IUFD was noted at amniocentesis. The pregnancy was subsequently terminated, and a 288-g female fetus was delivered with no phenotypic abnormalities. The umbilical cord had a karyotype of 46,XX (40/40 cells), and the placenta had a karyotype of 47,XX,+16 (40/40 cells). QF-PCR assays of the placenta confirmed a maternal origin of trisomy 16.
CONCLUSIONS: Mosaic trisomy 16 at amniocentesis can be associated with positive NIPT for trisomy 16, placental trisomy 16, IUGR, IUFD, cytogenetic discrepancy between cultured amniocytes and uncultured amniocytes, and prenatal progressive decrease of the aneuploid cell line.
摘要：
目的：我们在羊膜穿刺术中介绍了16三体，胎盘16三体，宫内生长受限（IUGR）的非侵入性产前检测（NIPT）阳性的妊娠，宫内胎儿死亡（IUFD），培养的羊膜细胞和未培养的羊膜细胞和未培养的羊膜细胞之间的细胞遗传学差异，和非整倍体细胞系的产前进行性减少。
方法：26岁，初产妇在妊娠17周时接受了羊膜穿刺术，因为在妊娠12周时16三体NIPT阳性。羊膜穿刺术显示核型为47，XX，+16[10]/46,XX[17],对从未培养的羊膜细胞提取的DNA进行同时阵列比较基因组杂交（aCGH）分析显示，ARR（16）×3[0.43]的结果与16三体的43％镶嵌性一致。她在妊娠19周时被转介接受遗传咨询，并且发现患有IUGR的胎儿的大小相当于妊娠16周。妊娠23周时，胎儿表现为羊水过少，胎儿心脏肿大和严重的IUGR（胎儿大小相当于妊娠20周）。重复羊膜穿刺术在培养的羊膜细胞中发现核型为46，XX（20/20集落），在未培养的羊膜细胞中通过aCGH发现镶嵌三体性16。未培养羊膜细胞的aCGH分析显示ARr16p13.3q24.3×2.3的结果，与16三体的30％（log2比率=0.2）镶嵌性一致。对从亲本血液和未培养的羊膜细胞中提取的DNA进行定量荧光聚合酶链反应（QF-PCR）测定，排除了单亲二体（UPD）16。亲本核型正常。在羊膜穿刺术中注意到IUFD。随后终止了妊娠，和一个288g的女性胎儿被交付，没有表型异常。脐带的核型为46,XX(40/40细胞),胎盘的核型为47,XX,+16（40/40细胞）。胎盘的QF-PCR测定证实了三体性16的母体起源。
结论：羊膜穿刺术中的马赛克三体性16与三体性16，胎盘三体性16，IUGR的阳性NIPT相关，IUFD,培养的羊膜细胞和未培养的羊膜细胞之间的细胞遗传学差异，和非整倍体细胞系的产前进行性减少。
方法：26岁，初产妇在妊娠17周时接受了羊膜穿刺术，因为在妊娠12周时16三体NIPT阳性。羊膜穿刺术显示核型为47，XX，+16[10]/46,XX[17],对从未培养的羊膜细胞提取的DNA进行同时阵列比较基因组杂交（aCGH）分析显示，ARR（16）×3[0.43]的结果与16三体的43％镶嵌性一致。她在妊娠19周时被转介接受遗传咨询，并且发现患有IUGR的胎儿的大小相当于妊娠16周。妊娠23周时，胎儿表现为羊水过少，胎儿心脏肿大和严重的IUGR（胎儿大小相当于妊娠20周）。重复羊膜穿刺术在培养的羊膜细胞中发现核型为46，XX（20/20集落），在未培养的羊膜细胞中通过aCGH发现镶嵌三体性16。未培养羊膜细胞的aCGH分析显示ARr16p13.3q24.3×2.3的结果，与16三体的30％（log2比率=0.2）镶嵌性一致。对从亲本血液和未培养的羊膜细胞中提取的DNA进行定量荧光聚合酶链反应（QF-PCR）测定，排除了单亲二体（UPD）16。亲本核型正常。在羊膜穿刺术中注意到IUFD。随后终止了妊娠，和一个288g的女性胎儿被交付，没有表型异常。脐带的核型为46,XX(40/40细胞),胎盘的核型为47,XX,+16（40/40细胞）。胎盘的QF-PCR测定证实了三体性16的母体起源。
结论：羊膜穿刺术中的马赛克三体性16与三体性16，胎盘三体性16，IUGR的阳性NIPT相关，IUFD,培养的羊膜细胞和未培养的羊膜细胞之间的细胞遗传学差异，和非整倍体细胞系的产前进行性减少。
