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 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 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*

OBJECTIVE: To explore the characteristics of copy number variation (CNV) within the Y chromosome azoospermia factor (AZF) region in patients with spermatogenesis disorders in the Shenzhen area. METHODS: A total of 123 patients with spermatogenesis disorders who had visited Shenzhen People's Hospital from January 2016 to October 2022 (including 73 patients with azoospermia and 50 patients with oligozoospermia) and 100 normal semen males were selected as the study subjects. The AZF region was detected with multiplex ligation-dependent probe amplification (MLPA), and the correlation between the CNV in the AZF region and spermatogenesis disorders was analyzed using the chi-square test or Fisher's exact test. RESULTS: 19 CNV were detected among 53 patients from the 223 samples, including 20 cases (27.40%, 20/73) from the azoospermia group, 19 cases (38%, 19/50) from the oligozoospermia group, and 14 cases (14%, 14/100) from the normal control group. In the azoospermia, oligozoospermia, and normal control groups, the detection rates for CNV related to the AZFa region (including AZFab and AZFabc) were 5.48% (4/73), 2.00% (1/50), and 0 (0/100), respectively. The detection rates for the AZFb region (including the AZFbc region) were 6.85% (5/73), 0 (0/50), and 0 (0/100), respectively. The detection rates for gr/gr deletions in the AZFc region were 2.74% (2/73), 6.00% (3/50), and 9.00% (9/100), respectively, and those for b2/b4 deletions in the AZFc region were 2.74% (2/73), 10.00% (5/50), and 0 (0/100), respectively. The detection rates for complex rearrangements in the AZFc region were 6.85% (5/73), 18.00% (9/50), and 3.00% (3/100), respectively. Statistical analysis showed no significant difference in the detection rate of gr/gr deletions between the three groups (Fisher's Exact Test value = 2.712, P = 0.249); the differences in the detection rate of b2/b4 deletions between the three groups were statistically significant (Fisher's Exact Test value = 9.489, P = 0.002); the differences in the detection rate of complex rearrangements in the AZFc region between the three groups were statistically significant (Fisher's Exact Test value = 9.493, P = 0.006). In this study, a rare AZFa region ARSLP1 gene deletion (involving SY86 deletion) was detected in a patient with oligozoospermia. CONCLUSION CNV in the AZFa and AZFb regions have a severe impact on spermatogenesis, but partial deletion in the AZFa region (ARSLP1 gene deletion) has a minor impact on spermatogenesis. The b2/b4 deletion and complex rearrangement in the AZFc region may be risk factors for male infertility. The gr/gr deletion may not serve as a risk factor for male infertility in the Shenzhen area.
Humans ; Male ; Azoospermia/genetics* ; DNA Copy Number Variations ; Oligospermia/genetics* ; Infertility, Male/genetics* ; Y Chromosome

OBJECTIVE: To explore the clinical and genetic characteristics of a Chinese pedigree affected with Multiple synostoses syndrome type 1 (SYNS1). METHODS: Clinical data of the proband and her family members were collected. Genomic DNA was extracted from peripheral blood samples. Whole-exome sequencing (WES) and whole-genome sequencing (WGS) were carried out for the proband and her parents. RESULTS: The pedigree has comprised of 14 members from three generations, of whom six had manifested hearing loss, with other symptoms including proximal symphalangism, hemicylindrical nose, amblyopia, strabismus, brachydactyly, incomplete syndactyly, which fulfilled the diagnostic criteria for SYNS1. WES had detected no pathogenic single nucleotide variants and insertion-deletion (InDel) in the coding region of the NOG gene, whilst copy number variation (CNV) analysis indicated that there was a heterozygous deletion involving the NOG gene. WGS revealed a heterozygous deletion (54171786_55143998) in 17q22 of the proband. The CNV was classified as pathogenic based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). CONCLUSION The heterozygous deletion in 17p22 involving the NOG gene probably underlay the pathogenesis of SYNS1 in this pedigree. Above finding has enriched the mutational spectrum of NOG. CNV should be considered when conventional sequencing has failed to detect any pathogenic variants in such patients.
Female ; Humans ; DNA Copy Number Variations ; East Asian People ; Pedigree ; Synostosis ; Phenotype

OBJECTIVE: To explore the clinical characteristics and genetic etiology of a Chinese pedigree affected with Alström syndrome. METHODS: A pedigree with 5 members affected with Alström syndrome who had visited the First Affiliated Hospital of Zhengzhou University in February 2021 was selected as the study subject. Clinical data of the pedigree were collected, and peripheral venous blood samples were collected for the extraction of genomic DNA. Genetic testing was carried out for the eldest daughter and third son through whole exome sequencing (WES). Candidate variant was verified by Sanger sequencing and bioinformatic analysis. RESULTS: The eldest daughter (14 years old) and the third son (11 years old) both had congenital nystagmus, amblyopia, growth retardation and type 2 diabetes. WES revealed that both had harbored homozygous c.3538A>T (p.Lys1180*) variant of the ALMS1 gene. Sanger sequencing confirmed that the father, mother, and second daughter were all heterozygous carriers. Based on the Guidelines for Genetic Variation and the Technical Standards for Interpretation and Reporting of Primary Copy Number Variations, the variant was predicted as pathogenic (PVS1+PM2_Supporting+PP4). CONCLUSION The homozygous c.3538A>T (p.Lys1180*) variant of the ALSM1 gene probably underlay the Alström syndrome in this pedigree, which has provided a reference for the clinical treatment.
Adolescent ; Child ; Humans ; Alstrom Syndrome/genetics* ; Diabetes Mellitus, Type 2 ; DNA Copy Number Variations ; East Asian People ; Pedigree ; Male ; Female

OBJECTIVE: To explore the genetic characteristics of a child with Focal segmental glomerulosclerosis and neurodevelopmental syndrome (FSGSNEDS). METHODS: A child with FSGSNEDS who had visited Shengli Oilfield Central Hospital on September 15, 2019 was selected as the study subject. Clinical data of the child was collected, and trio-whole exome sequencing (trio-WES), Sanger sequencing, chromosomal karyotyping analysis, and copy number variation sequencing (CNV-seq) were used to analyze the child and his parents. RESULTS: The child, a 3-year-old boy, had manifested developmental delay, nephrotic syndrome, and epilepsy. Trio-WES and Sanger sequencing showed that he has carried a heterozygous c.1375C＞T (p.Q459*) variant of the TRIM8 gene, for which both his parents were of the wild type. Based on guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was predicted to be pathogenic. No abnormality was found in the chromosomal karyotyping and CNV-seq results of the child and his parents. CONCLUSION The child was diagnosed with FSGSNEDS, for which the c.1375C＞T variant of the TRIM8 gene may be accountable.
Male ; Humans ; Child ; Child, Preschool ; DNA Copy Number Variations ; Glomerulosclerosis, Focal Segmental/genetics* ; Genomics ; Heterozygote ; Karyotyping ; Carrier Proteins ; Nerve Tissue Proteins

OBJECTIVE: To assess the value of non-invasive prenatal testing (NIPT) for the identification of numerical and structural chromosomal abnormalities and copy number variations (CNVs) in fetuses. METHODS: 46 197 pregnant women undergoing NIPT at the Prenatal Diagnosis Center of Chenzhou First People's Hospital from January 2018 to December 2021 were selected as the study subjects. Positive cases were subjected to chromosomal karyotyping and copy number variation sequencing (CNV-seq) following amniocentesis. RESULTS: Nearly 50% of common chromosomal aneuploidies were found in the elder pregnant women. Among these, sex chromosome aneuploidies were mainly found in pregnant women with advanced age as well as borderline risks by serological screening. Rare autosomal aneuploidies and CNVs were mainly found in those with borderline or high risks by serological screening. The positive predictive values (PPV) for fetal chromosomal abnormalities indicated by NIPT were as follows: T21 (92.37%, 109/118), T18 (53.85%, 14/26), sex chromosome aneuploidies (45.04%, 59/131), T13 (34.62%, 9/26), CNVs (29.17%, 14/48), and rare autosomal aneuploidies (2.60%, 2/77). CONCLUSION NIPT has a high detection rate for T21, T18, T13 and sex chromosome aneuploidies. It can also detect rare autosomal aneuploidies and CNVs, including some rare structural abnormalities, though verification is required by analyzing amniotic fluid samples.
Pregnancy ; Female ; Humans ; DNA Copy Number Variations ; Chromosome Aberrations ; Chromosome Disorders/genetics* ; Aneuploidy ; Fetus

OBJECTIVE: To analyze the characteristics of genetic variants among children with refractory epilepsy (RE). METHODS: One hundred and seventeen children with RE who had presented at the Affiliated Jinhua Hospital of Zhejiang University School of Medicine from January 1, 2018 to November 21, 2019 were selected as the study subjects. The children were divided into four groups according to their ages of onset: < 1 year old, 1 ~ 3 years old, 3 ~ 12 years old, and >= 12 years old. Clinical data and results of trio-whole exome sequencing were retrospectively analyzed. RESULTS: In total 67 males and 50 females were included. The age of onset had ranged from 4 days to 14 years old. Among the 117 patients, 33 (28.21%) had carried pathogenic or likely pathogenic variants. The detection rates for the < 1 year old, 1 ~ 3 years old and >= 3 years old groups were 53.85% (21/39), 12.00% (3/25) and 16.98% (9/53), respectively, with a significant difference among the groups (χ² = 19.202, P < 0.001). The detection rates for patients with and without comorbidities were 33.33% (12/36) and 25.93% (21/81), respectively (χ² = 0.359, P = 0.549). Among the 33 patients carrying genetic variants, 27 were single nucleotide polymorphisms (SNPs) or insertion/deletions (InDels), and 6 were copy number variations (CNVs). The most common mutant genes were PRRT2 (15.15%, 5/33) and SCN1A (12.12%, 4/33). Among children carrying genetic variants, 72.73% (8/11) had attained clinical remission after adjusting the medication according to the references. CONCLUSION 28.21% of RE patients have harbored pathogenic or likely pathogenic variants or CNVs. The detection rate is higher in those with younger age of onset. PRRT2 and SCN1A genes are more commonly involved. Adjusting medication based on the types of affected genes may facilitate improvement of the remission rate.
Infant ; Female ; Male ; Humans ; Child ; Infant, Newborn ; Child, Preschool ; DNA Copy Number Variations ; Drug Resistant Epilepsy/genetics* ; Retrospective Studies ; Polymorphism, Single Nucleotide