Prenatal diagnosis of a fetus with 46,XX (SRY positive) male syndrome / 中华医学遗传学杂志

OBJECTIVE@#To carry out genetic testing for a XXY fetus suggested by non-invasive prenatal testing (NIPT).@*METHODS@#G-banding karyotyping, fluorescence in situ hybridization (FISH) and chromosomal microarray analysis (CMA) were performed on amniocytes from the fetus. The genitalia of the fetus was also examined by Doppler ultrasonography. The result was verified with peripheral blood samples from its parents and a brother.@*RESULTS@#The fetus was found to have a 46,XX karyotype. CMA showed presence of sequences from Yp11.2 (2.635 Mb) and Yp11.31p11.2 (3.706 Mb). FISH assay suggested that the SRY fragment on Yp has translocated to Xpter. No karyotypic or pathogenic CNVs was detected in its parents and brother. The fetus was ultimately diagnosed with 46,XX (SRY positive) male syndrome.@*CONCLUSION@#The combination of G-banding karyotyping, FISH, and CMA is of great significance for attaining accurate prenatal diagnosis for this fetus.

The value of non-invasive prenatal testing for the identification of fetal chromosome aneuploidies / 中华医学遗传学杂志

Objective@#To assess the value of non-invasive prenatal testing (NIPT) for the identification of fetal chromosomal aneuploidies.@*Methods@#For 9470 pregnant women with a moderate-to-high risk by conventional serological screening or advanced maternal age, peripheral venous blood samples were collected and, following extraction of free fetal DNA, subjected to large-scale parallel sequencing on a Illumina Hiseq2000 platform. Those with a high risk by NIPT were validated by invasive prenatal diagnosis.@*Results@#Out of the 9470 samples, 194 cases (2.0%) were positive by NIPT testing. These included 50 trisomy 21, 11 trisomy 18, 17 trisomy 13, 44 other autosomal aneuploidies, 55 sex chromosomal aneuploidies, and 17 chromosomal copy number variations. As validated by amniotic fluid or umbilical blood chromosomal karyotyping analysis, NIPT has a false positive rate of 2.0%, 18.2%, 41.2%, 97.7%, 81.8%, 94.1%, respectively. The test has a sensitivity of 100% and a specificity of 98.79%.@*Conclusion@#For common chromosomal aneuploidies such as trisomy 21 and trisomy 18, NIPT has a good sensitivity and specificity, therefore has good value for clinical application.

The value of non-invasive prenatal testing for the identification of fetal chromosome aneuploidies / 中华医学遗传学杂志

OBJECTIVE@#To assess the value of non-invasive prenatal testing (NIPT) for the identification of fetal chromosomal aneuploidies.@*METHODS@#For 9470 pregnant women with a moderate-to-high risk by conventional serological screening or advanced maternal age, peripheral venous blood samples were collected and, following extraction of free fetal DNA, subjected to large-scale parallel sequencing on a Illumina Hiseq2000 platform. Those with a high risk by NIPT were validated by invasive prenatal diagnosis.@*RESULTS@#Out of the 9470 samples, 194 cases (2.0%) were positive by NIPT testing. These included 50 trisomy 21, 11 trisomy 18, 17 trisomy 13, 44 other autosomal aneuploidies, 55 sex chromosomal aneuploidies, and 17 chromosomal copy number variations. As validated by amniotic fluid or umbilical blood chromosomal karyotyping analysis, NIPT has a false positive rate of 2.0%, 18.2%, 41.2%, 97.7%, 81.8%, 94.1%, respectively. The test has a sensitivity of 100% and a specificity of 98.79%.@*CONCLUSION@#For common chromosomal aneuploidies such as trisomy 21 and trisomy 18, NIPT has a good sensitivity and specificity, therefore has good value for clinical application.

Fetal Emanuel syndrome: a case report / 中华围产医学杂志

We hereby reported the prenatal diagnosis of a case of fetal Emanuel syndrome. At 12+3 gestational weeks, ultrasound examination suggested that the fetal nuchal translucency thickness was 3.3 mm. At 24+2gestational weeks, the fetus was found with growth restriction, lateral ventriculomegaly (14 mm), broadened posterior cranial fossa (13 mm), right multicystic dysplastic kidney and doubled left renal pelvis by ultrasound. Karyotyping of both the fetus and the parents was performed using G banding, and showed that the fetus was 47, XX, +mar, the father was normal, while the mother was 46, XX, t(11;22)(q23;q11.2). Single-nucleotide polymorphism-array of the fetal cells in amniotic fluid suggested that the fetus had a partial duplication of chromosomes 22 and 11 at 22q11.1-q11.21 and 11q23.3-q25 and carried a marker chromosome +der(22)t(11;22) (q23.3;q11.21), based on which the fetus was eventually diagnosed as Emanuel syndrome. The pregnancy was terminated after genetic consultation.

Application of combined chromosomal karyotyping and BACs-on-Beads assay for the prenatal diagnosis of high-risk gravida from Ningbo / 中华医学遗传学杂志

<p><b>OBJECTIVE</b>To assess the value of combined chromosomal karyotyping and BACs-on-Beads(BoBs) assay for the prenatal diagnosis of high risk gravida from Ningbo.</p><p><b>METHODS</b>For 2779 women, results of conventional karyotyping analysis and BoBs assay were compared.</p><p><b>RESULTS</b>For common aneuploidies involving chromosomes 13, 18, 21, X and Y, the two methods have yielded a concordance rate of 98.78%. Eight cases detected with microduplication by BoBs were missed by karyotyping analysis. On the other hand, 17 structural chromosomal abnormalities, 10 chimeras and 1 triploidy detected by karyotyping analysis were missed by BoBs.</p><p><b>CONCLUSION</b>The BoBs technology has featured high throughput and rapidity, and can detect 9 microdeletion syndromes, which can improve the quality of prenatal diagnosis and provide an ideal complementary for conventional chromosomal karyotyping.</p>

Relationship between fetal karyotype and age of pregnancy / 中华检验医学杂志

Objective To evaluate the possibility of elevating the age line for pregnant women with advanced age to conducted amniocentesis .Methods A retrospective cohort study was performed .The information of 5 176 advanced age pregnant women in July 2003 to August 2015 from Ningbo Women and Children Hospital were collected and analyzed .Grouped the patients by age , using chi-square analysis , comparing the difference of abnormal rate of target chromosomes (13, 18, 21) and sex chromosomes (X and Y) between the adjacent two age groups .Results Total of 15 408 cases were screened.Among these, 262 cases were diagnosed with abnormal chromosome .The positive rate was 1.70%.Total of 5 176 advanced age pregnant women were included , 82 women were found with abnormal target chromosomes (13, 18, 21) and sex chromosome.The positive rate was 1.58%(82/5 176).For age groups, the positive rates were 0.95%(11/1 156), 0.94%(9/954), 0.87%(10/1 144), 2.16%(14/648), 2.16%(10/464), 2.51%(10/399) and 4.38%(18/411) respectively.Chi-square analysis results showed that the positive rate between group of 37 and 38 was significant difference (chi-square value of 5.181,P value of 0.023).There were no significant differences among all remained groups ( chi-square value: <0.001, 0.028, <0.001, 0.117, 2.129 respectively, P value: 0.985, 0.868, 0.995, 0.733, 0.145 respectively ) .Conclusion It is worthwhile to elevate the age of pregnant women up to 38 years old as the age line for the indications of amniotic fluid chromosome analysis .