Reasons for failure of noninvasive prenatal test for cell-free fetal DNA in maternal peripheral blood.

BACKGROUND: To explore reasons for the failure of noninvasive prenatal test (NIPT) for cell-free fetal DNA (cffDNA) in maternal peripheral blood, and discuss appropriate treatment schemes after the failure of the test. METHODS: Altogether 41,136 pregnant women participated in NIPT. Blood samples were taken again from pregnant women who failed the first blood collection upon their informed consent. Prenatal genetic counseling or prenatal diagnosis was recommended for pregnant women with final NIPT failure. RESULTS: The first failure rate of NIPT was 0.737% (303/41136), and the reason for the failure was the low ratio of cffDNA in 135 (44.6%) of the 303 pregnant women. After the second or third blood sampling, the final failure rate was 0.182% (75/41136). The low ratio of cffDNA was the main reason for test failure in 42 (56.0%) of the 75 pregnant women who finally failed NIPT, among whom 44 (58.7%) had underlying diseases, including 21 (47.7%) with more than two coexisting underlying diseases. Only 27 (36.0%) of the 75 pregnant women with NIPT failure underwent interventional prenatal diagnosis. CONCLUSIONS: The main reason for NIPT failure was the low ratio of cffDNA. Postponing the gestational weeks of blood collection may improve the success rate. Resampling and retesting upon informed consent in pregnant women who failed the first test could improve the success rate. For pregnant women who finally failed NIPT, it is suggested strengthening the genetic counseling, prenatal examination, and ultrasound evaluation, and carry out interventional prenatal diagnosis if necessary.

The prenatal diagnosis and prognosis of fetal right aortic arch and double aortic arch malformation: A single-center study.

AIM: This study aimed to characterize the pathological types, diagnosis, chromosomal abnormalities, and postnatal clinical manifestations of right and double aortic arch malformations in fetuses. METHODS: In this retrospective study, all fetuses diagnosed with right or double aortic arch anomalies for whom conventional two-dimensional echocardiography combined with spatio-temporal image correlation was performed at our tertiary referral center between December 2012 and December 2021 were included. RESULTS: In total, 234 fetuses with aortic arch abnormalities were identified. Forty-one cases lost to follow-up. One hundred ninety-three cases were included in this study. One hundred eighty-seven cases with right aortic arch. Six cases with double aortic arch. Most cases of right aortic arch with aberrant left subclavian artery (77/101, 76.2%) were isolated lesions, whereas most of those with mirror-image branching (45/75, 60%) were associated with intracardiac or extracardiac anomalies. Chromosomal abnormalities were screened prenatally in 113 fetuses with right aortic arch, among whom three with aberrant left subclavian artery (3/63, 4.8%) and eight with mirror-image branching (8/50, 16%) had chromosome anomalies (p < 0.05). Furthermore, three cases had microdeletion 22q11.2 and these were significantly associated with intracardiac malformations. CONCLUSIONS: Most cases of isolated right aortic arch do not present with clinical symptoms except isolated left subclavian artery and isolated left brachiocephalic trunk. In addition, the risk of chromosomal abnormalities in patients with isolated right aortic arch is very low. We recommend that pregnant women should be informed of the risks and benefits of undergoing invasive prenatal chromosomal detection.

A new and improved method of library preparation for non-invasive prenatal testing: plasma to library express technology.

OBJECTIVES: This study aims to develop a novel library preparation method, plasma to library express technology (PLET), to construct next-generation sequencing (NGS) libraries directly from plasma without cell-free DNA (cfDNA) isolation. METHODS: Peripheral blood samples (600) were obtained from a retrospective cohort of 300 pregnant women prior to invasive diagnostic testing. The samples were subsequently distributed between library preparation methodologies, with 300 samples prepared by PLET and 300 by conventional methods for non-invasive prenatal testing (NIPT) to screen for common trisomies using low-pass whole genome next generation sequencing. RESULTS: NIPT conducted on PLET libraries demonstrated comparable metrics to libraries prepared using conventional methods, including 100% sensitivity and specificity. CONCLUSIONS: Our study demonstrates the potential utility of PLET in the clinical setting and highlights its significant advantages, including dramatically reduced process complexity and markedly decreased turnaround time.

Intra- and peritumoral radiomics for predicting early recurrence in patients with high-grade serous ovarian cancer.

PURPOSE: To explore values of intra- and peritumoral CT-based radiomics for predicting recurrence in high-grade serous ovarian cancer (HGSOC) patients. METHODS: This study enrolled 110 HGSOC patients from our hospital between Aug 2017 and Apr 2021. All patients underwent contrast-enhanced CT scans before treatment. The least absolute shrinkage and selection operator (LASSO) regression was used to select radiomics features from intra- and peritumoral areas. Radiomics signatures were built based on selected features from Intra-RS, Peri-RS, and in Com-RS. A nomogram was constructed by combining radiomics signatures and clinical parameters with predictive potential. Receiver operating characteristics (ROC), calibration, and decision curve analyses (DCA) curves were used to evaluate performance of the nomogram. RESULTS: The intra- and peritumoral combined Com-RS showed effective ability in predicting recurrent HGSOC in the training (AUCs, Intra-RS vs. Peri-RS vs. Com-RS, 0.861 vs. 0.836 vs. 899) and validation (AUCs, Intra-RS vs. Peri-RS vs. Com-RS, 0.788 vs. 0.762 vs. 815) cohort. The Federation of International of FIGO stage, menstruation, and location were found to be strongly associated with tumor recurrence. The nomogram has the best predictive ability in the training (AUCs, Com-RS vs. clinical model vs. nomogram, 0.899 vs. 0.648 vs. 0.901) and validation (AUCs, Com-RS vs. clinical model vs. nomogram, 0.815 vs. 0.666 vs. 0.818) cohort. CONCLUSION: Our findings suggested values of intra- and peritumoral-based radiomics for predicting recurrent HGSOC. The constructed nomogram may be of importance in clinical application.

Radiomics for Detection of the EGFR Mutation in Liver Metastatic NSCLC.

RATIONALE AND OBJECTIVES: The research aims to investigate whether MRI radiomics on hepatic metastasis from primary nonsmall cell lung cancer (NSCLC) can be used to differentiate patients with epidermal growth factor receptor (EGFR) mutations from those with EGFR wild-type, and develop a prediction model based on combination of primary tumor and the metastasis. MATERIALS AND METHODS: A total of 130 patients were enrolled between Aug. 2017 and Dec. 2021, all pathologically confirmed harboring hepatic metastasis from primary NSCLC. The pyradiomics was used to extract radiomics features from intra- and peritumoral areas of both primary tumor and metastasis. The least absolute shrinkage and selection operator (LASSO) regression was applied to identify most predictive features and to develop radiomics signatures (RSs) for prediction of the EGFR mutation status. The receiver operating characteristic (ROC) curve analysis was performed to assess the prediction capability of the developed RSs. RESULTS: A RS-Primary and a RS-Metastasis were derived from the primary tumor and metastasis, respectively. The RS-Combine by combination of the primary tumor and metastasis achieved the highest prediction performance in the training (AUCs, RS-Primary vs. RS-Metastasis vs. RS-Combine, 0.826 vs. 0.821 vs. 0.908) and testing (AUCs, RS-Primary vs. RS-Metastasis vs. RS-Combine, 0.760 vs. 0.791 vs. 0.884) set. The smoking status showed significant difference between EGFR mutant and wild-type groups (p < 0.05) in the training set. CONCLUSION: The study indicates that hepatic metastasis-based radiomics can be used to detect the EGFR mutation. The developed multiorgan combined radiomics signature may be helpful to guide individual treatment strategies for patients with metastatic NSCLC.

MRI-Based Radiomics Nomogram as a Potential Biomarker to Predict the EGFR Mutations in Exon 19 and 21 Based on Thoracic Spinal Metastases in Lung Adenocarcinoma.

RATIONALE AND OBJECTIVES: Preoperative identifications of epidermal growth factor receptor (EGFR) mutation subtypes based on the MRI image of spinal metastases are needed to provide individualized therapy, but has not been previously investigated. This study aims to develop and evaluate an MRI-based radiomics nomogram for differentiating the exon 19 and 21 in EGFR mutation from spinal bone metastases in patients with primary lung adenocarcinoma. MATERIALS AND METHODS: A total of 76 patients underwent T1-weighted and T2-weighted fat-suppressed MRI scans were enrolled in this study, 38 were positive for EGFR mutation in exon 19 and 38 were in exon 21.MRI imaging features were extracted and selected from each MRI pulse sequence, and used to form the radiomics signature. A radiomics nomogram was developed integrating the radiomics signature and important clinical factors with receiver operating characteristic, calibration and decision curve analysis to assess the nomogram. Clinical characteristics were analyzed with Mann-Whitney U and Chi-Square tests to identify the most important factors. RESULTS: A total of 6 features were selected as the most discriminative predictors from the two MRI pulse sequences. The nomogram integrating the combined radiomics signature, age and CEA level generated good prediction performance in the training (AUCs, nomogram vs. combined radiomics signature vs. clinical model, 0.90 vs. 0.87 vs. 0.59) and validation (AUCs, nomogram vs. combined radiomics signature vs. clinical model, 0.88 vs. 0.86 vs. 0.72) cohort. DCA analysis confirmed the potential clinical utility of the nomogram. CONCLUSION: This study demonstrated that MRI features from spinal bone metastases can be used to prognosticate EGFR mutation subtypes in exon 19 and 21. The developed pre-treatment nomogram can potentially guide treatments for lung adenocarcinoma patients.

MRI-based radiomics analysis for predicting the EGFR mutation based on thoracic spinal metastases in lung adenocarcinoma patients.

PURPOSE: This study aims to develop and evaluate multi-parametric MRI-based radiomics for preoperative identification of epidermal growth factor receptor (EGFR) mutation, which is important in treatment planning for patients with thoracic spinal metastases from primary lung adenocarcinoma. METHODS: A total of 110 patients were enrolled between January 2016 and March 2019 as a primary cohort. A time-independent validation cohort was conducted containing 52 patients consecutively enrolled from July 2019 to April 2021. The patients were pathologically diagnosed with thoracic spinal metastases from primary lung adenocarcinoma; all underwent T1-weighted (T1W), T2-weighted (T2W), and T2-weighted fat-suppressed (T2FS) MRI scans of the thoracic spinal. Handcrafted and deep learning-based features were extracted and selected from each MRI modality, and used to build the radiomics signature. Various machine learning classifiers were developed and compared. A clinical-radiomics nomogram integrating the combined rad signature and the most important clinical factor was constructed with receiver operating characteristic (ROC), calibration, and decision curves analysis (DCA) to evaluate the prediction performance. RESULTS: The combined radiomics signature derived from the joint of three modalities can effectively classify EGFR mutation and EGFR wild-type patients, with an area under the ROC curve (AUC) of 0.886 (95% confidence interval [CI]: 0.826-0.947, SEN =0.935, SPE =0.688) in the training group and 0.803 (95% CI: 0.682-0.924, SEN = 0.700, SPE = 0.818) in the time-independent validation group. The nomogram incorporating the combined radiomics signature and smoking status achieved the best prediction performance in the training (AUC = 0.888, 95% CI: 0.849-0.958, SEN = 0.839, SPE = 0.792) and time-independent validation (AUC = 0.821, 95% CI: 0.692-0.929, SEN = 0.667, SPE = 0.909) cohorts. The DCA confirmed potential clinical usefulness of our nomogram. CONCLUSION: Our study demonstrated the potential of multi-parametric MRI-based radiomics on preoperatively predicting the EGFR mutation. The proposed nomogram model can be considered as a new biomarker to guide the selection of individual treatment strategies for patients with thoracic spinal metastases from primary lung adenocarcinoma.

Multiparametric MRI-Based Radiomics Approaches for Preoperative Prediction of EGFR Mutation Status in Spinal Bone Metastases in Patients with Lung Adenocarcinoma.

BACKGROUND: Preoperative prediction of epidermal growth factor receptor (EGFR) mutation status in patients with spinal bone metastases (SBM) from primary lung adenocarcinoma is potentially important for treatment decisions. PURPOSE: To develop and validate multiparametric magnetic resonance imaging (MRI)-based radiomics methods for preoperative prediction of EGFR mutation based on MRI of SBM. STUDY TYPE: Retrospective. POPULATION: A total of 97 preoperative patients with lumbar SBM from lung adenocarcinoma (77 in training set and 20 in validation set). FIELD STRENGTH/SEQUENCE: T1-weighted, T2-weighted, and T2-weighted fat-suppressed fast spin echo sequences at 3.0 T. ASSESSMENT: Radiomics handcrafted and deep learning-based features were extracted and selected from each MRI sequence. The abilities of the features to predict EGFR mutation status were analyzed and compared. A radiomics nomogram was constructed integrating the selected features. STATISTICAL TESTS: The Mann-Whitney U test and χ2 test were employed for evaluating associations between clinical characteristics and EGFR mutation status for continuous and discrete variables, respectively. Least absolute shrinkage and selection operator was used for selection of predictive features. Sensitivity (SEN), specificity (SPE), and area under the receiver operating characteristic curve (AUC) were used to evaluate the ability of radiomics models to predict the EGFR mutation. Calibration and decision curve analysis (DCA) were performed to assess and validate nomogram results. RESULTS: The radiomics signature comprised five handcrafted and one deep learning-based features and achieved good performance for predicting EGFR mutation status, with AUCs of 0.891 (95% confidence interval [CI], 0.820-0.962, SEN = 0.913, SPE = 0.710) in the training group and 0.771 (95% CI, 0.551-0.991, SEN = 0.750, SPE = 0.875) in the validation group. DCA confirmed the potential clinical usefulness of the radiomics models. DATA CONCLUSION: Multiparametric MRI-based radiomics is potentially clinical valuable for predicting EGFR mutation status in patients with SBM from lung adenocarcinoma. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY: 2.

Prenatal diagnosis of sex chromosomal inversion, translocation and deletion.

The aim of the present study was to perform comprehensive prenatal diagnosis using various detection techniques on a fetus in a high­risk pregnant woman, and to provide genetic counseling for the patient and her family so as to avoid birth defects. The routine karyotype analysis via amniocentesis, fluorescence in situ hybridization, and whole genome microarray technique were performed for the prenatal diagnosis of the fetus. The fetal karyotype was 46,X,ish der(X) inv(X)(p22.3q28)t(X;Y)(q28;q11.2)(XYqter+,SRY­,DXZ1+, RP11­64L19+,STS+,XYpter+); namely, one fetal X chromosome belonged to the derivative imbalanced chromosome and this chromosome demonstrated complex chromosomal rearrangements involving inversion, translocation and deletion. Notably, pericentric inversion between Xp22.3 and Xq28 was identified, and the chromosomal microarray technique confirmed that the long arm q28 of the derivative X chromosome had a 1.241­Mb deletion in Xq28, which included Online Mendelian Inheritance in Man genes such as coagulation factor VIII, glucose­6­phosphate dehydrogenase, inhibitor of nuclear factor­κB kinase subunit γ, trimethyllysine hydroxylase ε, Ras­related protein Rab­39B and chloride intracellular channel 2. In addition, this chromosome also exhibited the local translocation of fragment Yq11.21­q11.23, which did not include the sex determining region Y gene. This fetus demonstrated deletion, inversion and translocation syndrome, and may exhibit the corresponding clinical phenotypes (e.g., intellectual disability or general delayed development) (1) of such chromosome abnormalities after birth. Therefore, in prenatal diagnosis, a variety of genetic diagnostic techniques should be comprehensively used based on specific clinical situations, which may accurately reveal the nature, sources and manifestations of the derivative chromosome abnormalities and avoid the birth of children with defects.

[Prenatal diagnosis of a case with 46,XX,del(4),dup(21)].

OBJECTIVE: To investigate the genetic cause and prognosis of a fetus with a rare karyotype. METHODS: Fluorescence in situ hybridization (FISH) was used for verifying a structural chromosomal abnormality detected by conventional karyotyping analysis. Whole genome DNA microarray was used to analyze copy number variations carried by the fetus. RESULTS: The fetus was found to have a 46,XX,dup(21)(?q21q22) karyotype, which was verified by FISH analysis as repetition of chromosome 21 region, namely nuc ish 21q22×3. Whole genome DNA microarray confirmed that there was a 17.87 Mb duplication in the 21q21.3q22.3 region, which involved GATA1, JAK2 and ALL genes and spanned the Down syndrome region. The genes are implicated in craniofacial abnormalities, cardiac abnormalities, mental retardation, growth retardation, limb abnormalities. In addition, there was also an 8.43 Mb deletion in the 4p16.1p16.3 region, which involved FGFR3, LETM1, WHSC1 and WHSC2 and other 64 OMIM genes and spanned the Wolf-Hirschhorn syndrome region. The genes are implicated in growth retardation, craniofacial abnormalities, cardiac abnormalities, mental retardation, and hypotonia. After consultation, the family chose to terminate the pregnancy at 25th week of gestation. CONCLUSION: FISH can help to verify structural chromosome abnormalities suspected by conventional karyotyping analysis. Combined with whole genome microarray, these can determine copy number variation and its region containing the disease genes, and facilitate clinical analysis of the fetus.

[Detection of a fetus with paternally derived 2q37.3 microdeletion and 20p13p12.2 microduplication using whole genome microarray technology].

OBJECTIVE: To perform prenatal diagnosis for a fetus with multiple malformations. METHODS: The fetus was subjected to routine karyotyping and whole genome microarray analysis. The parents were subjected to high-resolution chromosome analysis. RESULTS: Fetal ultrasound at 28+4 weeks has indicated intrauterine growth restriction, left kidney agenesis, right kidney dysplasia, ventricular septal defect, and polyhydramnios. Chromosomal analysis showed that the fetus has a karyotype of 46,XY,der(2),der(20), t(2;20)(q37.3;p12.2), t(5;15) (q12.2;q25) pat. SNP array analysis confirmed that the fetus has a 5.283 Mb deletion at 2q37.3 and a 11.641 Mb duplication at 20p13p12.2. High-resolution chromosome analysis suggested that the father has a karyotype of 46,XY,t(2;20)(q37.3;p12.2),t(5;15)(q12.2;q25), while the mother has a normal karyotype. CONCLUSION: The abnormal phenotype of the fetus may be attributed to a 2q37.3 microdeletion and a 20p13p12.2 microduplication. The father has carried a complex translocation involving four chromosomes. To increase the chance for successful pregnancy, genetic diagnosis and/or assisted reproductive technology are warranted.

[Genetic and prenatal diagnosis of a pregnant women with mental retardation].

OBJECTIVE: To conduct genetic testing and prenatal diagnosis for a pregnant women with growth retardation, severe mental retardation, and a history of adverse pregnancies. METHODS: G-banded chromosome analysis, fluorescence in situ hybridization (FISH), and whole genome DNA microarray were used to analyze the patient and her fetus. RESULTS: The women was found to be a chimera containing two cell lines with 47 and 46 chromosomes, respectively. Both have involved deletion of 18q21.2q23. FISH analysis suggested that the cell line containing 47 chromosomes has harbored a chromosome marker derived from chromosome 15. The marker has contained chromosome 15p involving the SNRPN locus and part of 15q, which gave rise to a karyotype of 47,XX,del18q21.3,+ish mar D15Z1+ SNRPN+[82]/46,XX,del18q21.3[18]. Whole genome DNA microarray confirmed that a 3.044 Mb fragment from 15q11.2q12 was duplicated, which involved NIPA1, SNRPN and other 17 OMIM genes. Duplication of this region has been characterized by low mental retardation, autism, developmental delay. Meanwhile, there was a 17.992 Mb deletion at 18q21.33q23, which contained 39 OMIM genes including TNFRSF11A and PHLPP1. This fragment was characterized by mental retardation, developmental delay, short stature, and cleft palate. Whole genome microarray analysis confirmed that there was a 17.9 Mb deletion at 18q21.33q23, which has been implemented with mental retardation, general growth retardation, short stature, and cleft palate. After genetic counseling, the family decided to terminate the pregnancy at 21st week. CONCLUSION: Combined chromosome karyotyping, FISH, and whole genome DNA microarray can determine the origin of marker chromosomes and facilitate delineation of its correlation with the clinical phenotype.

[Analysis of relationship between patients with chromosomal translocation and the outcome of pregnancy].

OBJECTIVE: To explore the relationship between chromosome translocation and their phenotypic effect by analyzing the patients with loss pregnancy and avoiding fetuses with chromosomal abnormalities. METHODS: A total of 3067 cases with infertility or loss pregnancy were recruited to receive chromosome examination during January 2005 to December 2011 at Center of Prenatal Diagnosis, Peking University People's Hospital. Retrospective study was used to analyze the chromosome karyotypes and infertility or loss pregnancy. RESULTS: In 72 cases of patients with chromosome translocation, there were 17 pregnancies with homology translocation in fetus. And the numbers of patients with loss pregnancy and sex apparatus malformations were 40 and 15 respectively. CONCLUSION: Chromosome translocation plays an important role in patients with loss pregnancy or infertility. And chromosome examination should be performed to exclude the possibility of chromosome abnormities in patients with obstinate infertility.

Cytogenetic analysis of 355 cases of fetal loss in different trimesters.

OBJECTIVE: We estimated the success rates of cytogenetic analyses in different tissue samples after intrauterine fetal deaths and analyzed the value of cytogenetic testing for determining the causes. METHODS: Women with intrauterine fetal deaths (occurring at > 10 weeks of gestation) were offered either invasive testing before medical induction of labor, or solid tissue biopsy diagnosis after delivery. RESULTS: A total cohort of 355 intrauterine fetal deaths was studied. During antepartum examinations, invasive procedures included amniocentesis (AMC), chorionic villus sampling (CVS) and umbilical cord (UBC) sampling. During postpartum examinations, samples were taken from unfixed specimens of fetal skin, placenta and other tissues. Chromosomal abnormalities were observed in 22 fetal deaths for which cytogenetic analyses were successful. Logistic regression analysis identified antepartum invasive sampling [P = 0.000, odds ratio (OR) 31.125, 95% confidence interval (CI) 14.265-67.908] to be associated with a high cytogenetic success rate and older age with fetal deaths (P = 0.104, OR 0.487, 95% CI 0.204-1.160) not to be associated with a high chromosomal abnormality. In the patients with recurrent pregnancy loss, the chromosomal abnormality rate of 18.6% of spontaneous abortions has not been significantly more than that of fetal deaths 11.5% (P = 0.437). CONCLUSION: Parents should be counseled on all aspects of cytogenetic analysis after fetal death. Antepartum testing after pregnancy loss is recommended.

[Molecular and prenatal diagnosis of a pedigree with spinocerebellar ataxia].

OBJECTIVE: To identify the type of a pedigree with spinocerebellar ataxia, and carry out asymptomatic carrier detection and prenatal diagnosis. METHODS: The blood samples of two patients in the spinocerebellar ataxia pedigree were collected. Based on the clinical characteristics of the pedigree and the disease incidence in China, the regions containing the CAG repeat of the SCA1, SCA2 and SCA3/MJD genes were amplified by polymerase chain reaction (PCR). The numbers of CAG repeats in the normal and abnormal allele fragments were identified by using agarose gel electrophoresis and DNA sequencing. We further carried out tests on the children of the patients and fetus to identify the presence of the abnormal allele. RESULTS: The numbers of CAG repeat in the SCA1 and SCA2 genes were in the normal range. The CAG repeat number in one allele of SCA3/MJD gene was in the normal range, while that in the other allele was in the abnormal range. One of the children of the patients and the fetus carried the abnormal allele. CONCLUSION: It was confirmed that the pedigree was SCA3/MJD by gene diagnosis. One of the children of the patients was asymptomatic carrier and the fetus also carried the abnormal allele.

[Chromosome abnormalities and congenital heart diseases: a retrospective on 49 cases].

OBJECTIVE: To investigate the association between congenital heart diseases and chromosome abnormalities. METHODS: Patients with congenital heart diseases who underwent chromosome examinations during Jan 2006 and Dec. 2009 in the Center of Prenatal Diagnosis of Beijing University People's Hospital were recruited in the study. The association between chromosome karyotypes and types of congenital heart diseases was analyzed. RESULTS: Among the 49 patients with congenital heart diseases, trisomy 21 was established in 11 cases, trisomy 18 in 6 cases, trisomy 13 in 6 cases, trisomy 14 in 1 cases, trisomy 16 in 3 cases, trisomy 8 in 1 cases, trisomy 22 in 1 cases, sex chromosomal abnormalities in 8 cases, triploid in 2 cases, partial chromosomal trisomy in 8 cases, and 46,XX/XY, 5p-- in 2 cases. CONCLUSION: Chromosome abnormalities are associated with congenital heart diseases. Different abnormal chromosome karyotypes contribute to different types of congenital heart diseases. Prenatal chromosome examinations could be undertaken to detect congenital heart diseases.

Prenatal cytogenetic diagnosis study of 2782 cases of high-risk pregnant women.

BACKGROUND: Prenatal diagnoses are extremely advantageous for pregnant women with high-risk indicators and can help prevent the birth of malformed infants. However, no large-scale statistical study analyzing the correlation between fetal chromosome disorders and abnormal indicators during pregnancy has been done in China. The objectives of this study were to diagnose and analyze fetal chromosome abnormalities, determine the feasibility of the various prenatal test methods and establish diagnostic guidelines for the early, middle, and late trimesters. METHODS: From January 2004 to May 2009, 2782 pregnant women at high-risk underwent prenatal diagnoses. Categorized data expressed as either actual counts or percentages were analyzed by the chi-square or Fisher's exact test. Chorionic villus sampling was performed in the early-trimester (10 - 12 weeks of gestation), amniocentesis in mid-trimester (16 - 28 weeks of gestation), and umbilical cord blood collection in mid- or late-trimester (16 - 37 weeks of gestation). In 51 cases either autopsy samples from intrauterine fetal deaths or placental tissues from aborted fetuses were tested. RESULTS: Chromosomal abnormalities were observed in 3.99% (111/2782) of the samples. Overall, the success rate of cytogenetic analysis for high-risk pregnancy groups was 98.17% (2731/2782). It was significantly less successful when used to analyze data from the chorionic villus sampling compared with that from amniocentesis and umbilical cord blood (P = 0.000). Abnormal chromosome carriers had the highest percentage of abnormal chromosomes (67.86%) when compared with chromosomal abnormalities in patients with ultra-sonographic "soft markers" (11.81%), advanced maternal age (4.51%) and those who had positive serum screening results (P = 0.000). CONCLUSIONS: Invasive prenatal diagnostic techniques are feasible tools for confirming fetal chromosomal abnormalities. Abnormal chromosomes detected in one of the parents carrying abnormal chromosome, ultrasound soft markers, advanced maternal age or positive serum screening results were associated with a higher frequency of fetal genetic diseases.

The expression of Gli3, regulated by HOXD13, may play a role in idiopathic congenital talipes equinovarus.

BACKGROUND: Idiopathic congenital talipes equinovarus (ICTEV) is a congenital limb deformity. Based on extended transmission disequilibrium testing, Gli-Kruppel family member 3 (Gli3) has been identified as a candidate gene for ICTEV. Here, we verify the role of Gli3 in ICTEV development. METHODS: Using the rat ICTEV model, we analyzed the differences in Gli3 expression levels between model rats and normal control rats. We used luciferase reporter gene assays and ChIP/EMSA assays to analyze the regulatory elements of Gli3. RESULTS: Gli3 showed higher expression levels in ICTEV model rats compared to controls (P < 0.05). We identified repressor and activator regions in the rat Gli3 promoter. The Gli3 promoter also contains two putative Hoxd13 binding sites. Using EMSA, the Hoxd13 binding site 2 was found to directly interact with Hoxd13 in vitro. ChIP assays of the Hoxd13-Gli3 promoter complex from a developing limb confirmed that endogenous Hoxd13 interacts with this region in vivo. CONCLUSION: Our findings suggest that HoxD13 directly interacts with the promoter of Gli3. The increase of Gli3 expression in ICTEV model animal might result from the low expression of HoxD13.

[Gene diagnosis for spinal muscular atrophy and its application study].

OBJECTIVE: To establish an effective testing system for gene diagnosis, carrier detection and prenatal diagnosis for spinal muscular atrophy (SMA). METHODS: Twenty-six patients with SMA were directly tested with PCR-RFLP for exon 7 deletion in the SMN1 gene. Carrier detection was carried out with multi-PCR-DHPLC. Amniotic fluid was taken at the middle stage of gestation from pregnant women who had given birth to affected children. RESULTS: Twenty-five out of 26 patients were diagnosed as having SMN1 gene deletion. Fifty-two of their parents were found to be carriers of exon 7 deletion. Eight of 20 fetuses were diagnosed as having SMN1 gene deletion by PCR-RFLP. CONCLUSION: PCR-RFLP and multi-PCR-DHPLC techniques can provide rapid diagnosis for exon 7 deletion detection and carrier detection. PCR-RFLP may also be adapted for prenatal gene diagnosis of exon 7 deletion in SMN1 gene.

[Application study on inversion diagnosis of F8 gene in hemophilia A].

OBJECTIVE: To establish an effective method of genetic diagnosis on hemophilia A (HA) by detecting the inversion mutation in intron 22 of F8 gene. METHODS: Intron 22 inversion mutation in F8 gene was detected by using long distance-polymerase chain reaction (LD-PCR) and inversion-PCR (I-PCR) in 31 HA patients. The mothers of HA patients with intron 22 inversion mutation were selected to carrier diagnosis and amniotic fluid of the pregnant women with inversion mutation was collected at intermediate stage of gestation, and used to prenatal genetic diagnosis. RESULTS: Seven patients showed F8 gene inversion mutation in thirty-one patients. Three in four mothers of HA patients with intron 22 inversion mutation were diagnosed as carriers. The prenatal diagnosis result indicated that the fetus conceived in the HA-carrier woman was normal individual. CONCLUSION: The detection of intron 22 inversion mutation by LD-PCR and I-PCR is time-saving, and can be used in prenatal diagnosis on HA.