The elucidation of resources pertaining to the Chimonanthus praecox varieties and the establishment of a fingerprint serve as crucial underpinnings for advancing scientific inquiry and industrial progress in relation to C. praecox. Employing the SSR molecular marker technology, an exploration of the genetic diversity of 175 C. praecox varieties (lines) in the Yanling region was conducted, and an analysis of the genetic diversity among these varieties was carried out using the UPDM clustering method in NTSYSpc 2.1 software. We analyzed the genetic structure of 175 germplasm using Structure v2.3.3 software based on a Bayesian model. General linear model (GLM) association was utilized to analyze traits and markers. The genetic diversity analysis revealed a mean number of alleles (Na) of 6.857, a mean expected heterozygosity (He) of 0.496 3, a mean observed heterozygosity (Ho) of 0.503 7, a mean genetic diversity index of Nei՚s of 0.494 9, and a mean Shannon information index of 0.995 8. These results suggest that the C. praecox population in Yanling exhibits a rich genetic diversity. Additionally, the population structure and the UPDM clustering were examined. In the GLM model, a total of fifteen marker loci exhibited significant (P < 0.05) association with eight phenotypic traits, with the explained phenotypic variation ranging from 14.90% to 36.03%. The construction of fingerprints for C. praecox varieties (lines) was accomplished by utilizing eleven primer pairs with the highest polymorphic information content, resulting in the analysis of 175 SSR markers. The present study offers a thorough examination of the genetic diversity and SSR molecular markers of C. praecox in Yanling, and establishes a fundamental germplasm repository of C. praecox, thereby furnishing theoretical underpinnings for the selection and cultivation of novel and superior C. praecox varieties, varietal identification, and resource preservation and exploitation.
Bayes Theorem ; Biomarkers ; Phenotype ; Cluster Analysis ; Genetic Variation

After the promulgation of the first edition of expert consensus on the application of chromosomal microarray analysis (CMA) technology in prenatal diagnosis in 2014, after 8 years of clinical and technical development, CMA technology has become a first-line diagnosis technology for fetal chromosome copy number deletion or duplication abnormalities, and is widely used in the field of prenatal diagnosis in China. However, with the development of the industry and the accumulation of experience in case diagnosis, the application of CMA technology in many important aspects of prenatal diagnosis, such as clinical diagnosis testimony, data analysis and genetic counseling before and after testing, needs to be further standardized and improved, so as to make the application of CMA technology more in line with clinical needs. The revision of the guideline was led by the National Prenatal Diagnostic Technical Expert Group, and several prenatal diagnostic institutions such as Peking Union Medical College Hospital were commissioned to write, discuss and revise the first draft, which was discussed and reviewed by all the experts of the National Prenatal Diagnostic Technical Expert Group, and was finally formed after extensive review and revision. This guideline is aimed at the important aspects of the application of CMA technology in prenatal diagnosis and clinical diagnosis, from the clinical application of evidence, test quality control, data analysis and interpretation, diagnosis report writing, genetic counseling before and after testing and other work specifications are elaborated and introduced in detail. It fully reflects the integrated experience, professional thinking and guidance of the current Chinese expert team on the prenatal diagnosis application of CMA technology. The compilation of the guideline for the application of CMA technology in prenatal diagnosis will strive to promote the standardization and advancement of prenatal diagnosis of fetal chromosome diseases in China.
Female ; Humans ; Pregnancy ; Asian People ; Chromosome Aberrations ; Chromosome Deletion ; Chromosome Duplication/genetics* ; DNA Copy Number Variations/genetics* ; Fetal Diseases/genetics* ; Genetic Counseling ; Microarray Analysis ; Prenatal Care ; Prenatal Diagnosis ; Practice Guidelines as Topic

Objective To explore the clinical significance of non-invasive prenatal testing(NIPT)for fetal chromosomal abnormalities in the cases of twin pregnancy and its relationship with age and other related factors.Methods A total of 3733 women with twin pregnancy of 12-26⁺⁶ weeks who voluntarily underwent NIPT in the Ningbo Women and Children's Hospital from January 2018 to December 2022 were selected.The results of NIPT and amniocentesis were compared and all the participants were followed up.The detection rate of chromosomal abnormalities by NIPT was calculated,and its correlations with age,gestational weeks,chorionicity,and pregnancy type were analyzed.Results Among the 3733 cases,71 cases of fetal chromosome abnormality were indicated by NIPT,including 13 cases of trisomy 21,19 cases of trisomy 18,5 cases of trisomy 13,18 cases of sex chromosome abnormality,and 16 cases of chromosome microdeletion/duplication(excluding 21,18,13,and sex chromosomes),among which 34 cases were true positive and 37 cases were false positive.The overall sensitivity,specificity,and positive predictive value(PPV)of NIPT for chromosomal abnormalities in the cases of twin pregnancy were 100%,98.99%,and 47.89%(34/71),respectively.NIPT showed the sensitivity,specificity,and PPV of 100%,99.78%,and 78.38%(29/37)for trisomy 21,18,and 13,100%,99.56%,and 16.67%(3/18)for sex chromosome abnormalities,and 100%,99.62%,and 12.5%(2/16)for chromosome microdeletion/duplication,respectively.In the age group of ≥40 years,the NIPT for chromosomal abnormalities showed the PPV of 66.67%,the sensitivity of 100%,and the misdiagnosis rate of 30%。However,the NIPT for trisomy 21,18,and 13 showed the PPV of 100%,the misdiagnosis rate of 0,and the sensitivity and specificity of 100%.In terms of grouping based on gestational weeks,the NIPT for chromosomal abnormalities showed the highest PPV(51.28%)in the women with twin pregnancy for 14-17⁺⁶ weeks,followed by that(50.00%)in the women with twin pregnancy for 22-26⁺⁶ weeks;the NIPT for trisomy 21,18,and 13 showed the highest PPV of 94.74% in the gestation group of 14-17⁺⁶ weeks,followed by that(83.33%)in the gestation group of 18-21⁺⁶ weeks.The rate of dichorionic diamniotic twins was higher in assisted pregnancies than in natural pregnancies,and NIPT showed the same detection efficiency for dichorionic diamniotic twins and monochorionic diamniotic twins and the same detection efficiency for different pregnancy types.Conclusions NIPT has high accuracy in the diagnosis of twin pregnancy and high sensitivity and high specificity for different ages and gestational weeks,especially for trisomy 21,18,and 13.NIPT is suitable for assisted pregnancy and natural pregnancy,and it is of high value in clinical application.However,extensive application needs a large population-based study.
Pregnancy ; Child ; Female ; Humans ; Adult ; Down Syndrome/genetics* ; Pregnancy, Twin ; Prenatal Diagnosis ; Trisomy ; Chromosome Aberrations

To explore the genetic diversity of Asarum sieboldii this study developed SSR markers based on transcriptome sequencing results and five populations of A.sieboldii from different regions were used as samples for genetic diversity assessment using software such as GenALEx 6.5, NTSYS 2.1, and Structure 2.3.4. The results showed that 16 SSR markers with high polymorphism and good repeatability were selected from the A.sieboldii transcriptome. Primers designed based on the flanking sequences of these markers successfully amplified 56 polymorphic fragments from 150 individual samples of the five A.sieboldii populations. On average, each primer amplified 3.5 polymorphic fragments, ranging from 2 to 8. The mean values of expected heterozygosity(H_e), Shannon's diversity index(I), Nei's gene diversity index(H), and the polymorphic information content(PIC) were 0.172, 0.281, 0.429, and 0.382, respectively. The mean population differentiation coefficient(F_(ST)) was 0.588, consistent with the analysis of molecular variance(AMOVA) results, which indicated greater genetic variation among A.sieboldii populations(69%) than that within populations(31%). The percentage of polymorphic loci(PPL) ranged from highest to lowest as SNJ>LN>SY>SZ>TB. Principal coordinate analysis(PCoA) and UPGMA clustering analysis further revealed genetic clustering of A.sieboldii individuals based on their geographical distribution, consistent with the results of the structure clustering analysis. In summary, the SSR markers developed from the transcriptome effectively assessed the genetic differentiation and population structure of natural A.sieboldii populations, revealing a relatively low genetic diversity in A.sieboldii, with genetic variation primarily observed at the population level and a correlation between population differentiation and geographic distance.
Humans ; Genetic Variation ; Asarum ; Transcriptome/genetics* ; Microsatellite Repeats/genetics* ; Phylogeny

ACGS Best Practice Guidelines for Variant Classification in Rare Disease 2020, a supplementary practical guidelines, is based on the Standards and Guidelines for the Interpretation of Sequence Variations issued by the American Society for Medical Genetics and Genomics (ACMG) and the Association of Molecular Pathology (AMP) in 2015 by the British Medical Genetics Society under the Clinical Genomics Society (ACGS), and has integrated the detailed rules of standards developed by the ClinGen Sequence Variant Interpretation (SVI) Working Group by 2020. The further development of the ACMG/AMP guidelines is currently undertaken by the ClinGen SVI working group in the United States, which focuses on the classification of high penetrance and protein coding variants. ClinGen has established many expert panels on variants for specific diseases which required various evidence thresholds and is currently developing disease/gene specific guidelines. The British Medical Genetics Society has collected and integrated information on the guidelines for sequence variation classification and their extended rules, forming its own "2020 ACGS Best Practice Guidelines for Rare Disease Variation Classification" and is regularly updating it. The author has translated and summarized it for the reference of Chinese Medical Genetics Practitioners.
Humans ; Genetic Testing ; Genetic Variation ; Genome, Human ; Rare Diseases/genetics* ; China

OBJECTIVE: To validate a fetus with high risk for trisomy 13 suggested by non-invasive prenatal testing (NIPT). METHODS: The fetus was selected as the study subject after the NIPT detection at Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences on February 18, 2019. Clinical data of the pregnant woman was collected. Fluorescence in situ hybridization (FISH), chromosomal karyotyping analysis and chromosomal microarray analysis (CMA) were carried out on amniotic fluid and umbilical cord blood and the couple's peripheral blood samples. Copy number variation sequencing (CNV-seq) was also performed on the placental and amniotic fluid samples following induced labor. RESULTS: The pregnant woman, a 38-year-old G4P1 gravida, was found to have abnormal fetal development by prenatal ultrasonography. NIPT test suggested that the fetus has a high risk for trisomy 13. Chromosomal karyotyping analysis of fetal amniotic fluid and umbilical cord blood were 46,XN,add(13)(p10). The result of CMA was arr[hg19]1q41q44(223937972_249224684)×3, with the size of the repeat fragment being approximately 25.29 Mb, the fetal karyotype was thereby revised as 46,XN,der(13)t(1;13)(q41;p10). Chromosomal karyotyping analysis and CMA of the parents' peripheral blood samples showed no obvious abnormality. The CNV-seq analysis of induced placenta revealed mosaicisms of normal karyotype and trisomy 13. The CNV-seq test of induced amniotic fluid confirmed a duplication of chr1:22446001_249220000 region spanning approximately 24.75 Mb, which was in keeping with the CMA results of amniotic fluid and umbilical cord blood samples. CONCLUSION NIPT may yield false positive result due to placenta mosaicism. Invasive prenatal diagnosis should be recommended to women with a high risk by NIPT test. And analysis of placenta can explain the inconsistency between the results of NIPT and invasive prenatal diagnosis.
Humans ; Female ; Pregnancy ; Trisomy 13 Syndrome/genetics* ; DNA Copy Number Variations ; Placenta ; Chromosomes, Human, Pair 1 ; In Situ Hybridization, Fluorescence ; Prenatal Diagnosis/methods* ; Fetus ; Amniotic Fluid ; Chromosome Aberrations ; Trisomy/genetics*

OBJECTIVE: To assess the value of non-invasive prenatal testing (NIPT) for detecting fetal chromosomal microdeletion/microduplication syndromes by carrying out prenatal diagnoses for two fetuses with Xp22.31 microdeletion indicated by NIPT. METHODS: Two pregnant women suspected for fetal Xp22.31 microdeletion syndrome who presented at Zaozhuang Maternal and Child Health Care Hospital on December 5, 2017 and October 15, 2020 were selected as the study subjects. Clinical data of the two women were collected, and peripheral venous blood samples were collected for NIPT testing. Amniotic fluid samples were taken for G-banding chromosomal karyotyping analysis and copy number variation sequencing (CNV-seq) for fetus 1, while G-banding chromosomal karyotyping and single nucleotide polymorphism microarray analysis (SNP array) were carried out for fetus 2. Peripheral venous blood samples of couple 1 were collected for CNV-seq to verify the origin of copy number variation . RESULTS: NIPT indicated that fetus 1 had harbored a 1.3 Mb deletion in the Xp22.31 region, while G-banding chromosomal karyotyping had found no abnormality. CNV-seq analysis verified the fetus to be seg[GRCh37]del(X)(p22.31)chrX:g.6800001_7940000del, with a 1.14 Mb deletion at Xp22.31, which was derived from its mother. NIPT indicated that fetus 2 had harbored a 1.54 Mb deletion in the Xp22.31 region, while G-banding chromosomal karyotyping had found no abnormality. SNP array analysis indicated arr[GRCh37]Xp22.31(6458940_8003247)×0, with a 1.54 Mb deletion in Xp22.31 region. CONCLUSION NIPT not only has a good performance for detecting fetal trisomies 21, 18 and 13, but also has the potential for detecting chromosomal microdeletion/microduplications. For high risk fetuses indicated by NIPT, prenatal diagnosis needs to be carry out to verify the chromosomal abnormalities.
Child ; Female ; Pregnancy ; Humans ; DNA Copy Number Variations ; Prenatal Diagnosis ; Down Syndrome/diagnosis* ; Chromosome Aberrations ; Fetus

OBJECTIVE: To assess the value of non-invasive prenatal testing (NIPT) for trisomy 21 (T21), trisomy 18 (T18), trisomy 13 (T13), sex chromosome aneuploidies, chromosomal microdeletions and microduplications using cell-free fetal DNA from peripheral blood samples of pregnant women. METHODS: A total of 15 237 pregnant women who had undergone NIPT testing at the Maternity and Child Health Care Hospital of Zaozhuang from February 2015 to December 2021 were enrolled in this study. For those with a high risk by NIPT, amniotic fluid samples were collected for G-banding chromosomal karyotyping analysis and chromosomal microarray analysis to verify the consistency of NIPT with results of prenatal diagnosis. All of the women were followed up by telephone for pregnancy outcomes. RESULTS: Among the 15 237 pregnant women, 266 (1.75%) were detected with a high risk for fetal chromosomal abnormality were detected. Among these, 79 (29.7%) were at a high risk for T21, 26 (9.77%) were at a high risk for T18, 9 (3.38%) were at a high risk for T13, 74 (27.82%) were at a high risk for sex chromosome aneuploidies, 12 (4.51%) were at a high risk for other autosomal aneuploidies, and 66 (24.81%) were at a high risk for chromosomal microdeletions or microduplications. 217 women had accepted invasive prenatal diagnosis and respectively 50, 13, 1, 25, 1 and 18 were confirmed with T21, T18, T13, sex chromosome aneuploidies, autosomal aneuploidies and microdeletions/microduplications, and the positive predictive values were 75.76%, 68.42%, 11.11%, 40.32%, 10% and 35.29%, respectively. For 13 042 women (85.59%), the outcome of pregnancy were successfully followed up. During the follow-up, one false negative case of T21 was discovered. No false positive cases for T13 and T18 were found. CONCLUSION NIPT has a sound performance for screening T13, T18 and T21, and is also valuable for screening other autosomal aneuploidies, sex chromosome aneuploidies and chromosomal microdeletions/microduplications.
Child ; Female ; Pregnancy ; Humans ; Retrospective Studies ; Cell-Free Nucleic Acids ; Chromosome Disorders/genetics* ; Prenatal Diagnosis/methods* ; Down Syndrome/genetics* ; Sex Chromosome Aberrations ; Trisomy 18 Syndrome/genetics* ; Trisomy 13 Syndrome/diagnosis* ; Aneuploidy ; DNA/genetics* ; Trisomy/genetics*

OBJECTIVE: To retrospectively analyze sex chromosomal abnormalities and clinical manifestations of children with disorders of sex development (DSD). METHODS: A total of 14 857 children with clinical features of DSD including short stature, cryptorchidism, hypospadia, buried penis and developmental delay were recruited from Zhengzhou Children's Hospital from January 2013 to March 2022. Fluorescence in situ hybridization (FISH) and chromosomal karyotyping were carried out for such children. RESULTS: In total 423 children were found to harbor sex chromosome abnormalities, which has yielded a detection rate of 2.85%. There were 327 cases (77.30%) with Turner syndrome and a 45,X karyotype or its mosaicism. Among these, 325 were females with short stature as the main clinical manifestation, 2 were males with short stature, cryptorchidism and hypospadia as the main manifestations. Sixty-two children (14.66%) had a 47,XXY karyotype or its mosaicism, and showed characteristics of Klinefelter syndrome (KS) including cryptorchidism, buried penis and hypospadia. Nineteen cases (4.49%) had sex chromosome mosaicisms (XO/XY), which included 11 females with short stature, 8 males with hypospadia, and 6 cases with cryptorchidism, buried penis, testicular torsion and hypospadia. The remainder 15 cases (3.55%) included 9 children with a XYY karyotype or mosaicisms, with main clinical manifestations including cryptorchidisms and hypospadia, 4 children with a 47,XXX karyotype and clinical manifestations including short stature and labial adhesion, 1 child with a 46,XX/46,XY karyotype and clinical manifestations including micropenis, hypospadia, syndactyly and polydactyly, and 1 case with XXXX syndrome and clinical manifestations including growth retardation. CONCLUSION Among children with DSD due to sex chromosomal abnormalities, sex chromosome characteristics consistent with Turner syndrome was most common, among which mosaicism (XO/XX) was the commonest. In terms of clinical manifestations, the females mainly featured short stature, while males mainly featured external genital abnormalities. Early diagnosis and treatment are particularly important for improving the quality of life in such children.
Humans ; Male ; Female ; Turner Syndrome/genetics* ; In Situ Hybridization, Fluorescence ; Cryptorchidism ; Hypospadias ; Retrospective Studies ; Quality of Life ; Sex Chromosome Aberrations ; Karyotyping ; Mosaicism ; Disorders of Sex Development/genetics*

OBJECTIVE: To assess the value of combined copy number variation sequencing (CNV-seq) and chromosomal karyotyping for the diagnosis of amniocytic mosaicisms, in addition with a literature review. METHODS: Forty cases of amniocytic mosaicisms detected at the Genetic and Prenatal Diagnosis Center of the First Affiliated Hospital of Zhengzhou University from January 2018 to December 2021, in addition with 245 mosaicisms retrieved from 11 recent literature were evaluated in terms of detection rate, consistency rate, and pregnancy outcomes. RESULTS: The detection rate of amniocytic mosaicisms was 0.46% (40/8 621) in our center. And its consistency rate with chromosomal karyotyping was 75.0% (30/40). After genetic counseling, 30 (75.0%) couples had opted to terminate the pregnancy, 5 (12.5%) had decided to continue with the pregnancy, 3 (7.5%) fetuses were born alive, and 2 cases (5.0%) were lost in touch. By contrast, 245 cases (0.39%) of mosaicisms were identified among 63 577 amniotic samples, with a consistency rate of 62.8% (103/164) with other techniques. Among these, 114 cases (55.1%) were terminated, 75 (36.2%) were born alive, and 18 (8.7%) were lost during the follow up. CONCLUSION Combined CNV-seq and chromosomal karyotyping has a high value for the detection of amniotic mosaicisms.
Pregnancy ; Female ; Humans ; Mosaicism ; Chromosome Disorders/genetics* ; DNA Copy Number Variations ; Chromosome Aberrations ; Karyotyping ; Prenatal Diagnosis/methods*