OBJECTIVE: To provide prenatal diagnosis, pedigree analysis and genetic counseling for a pregnant woman who had given birth to a child featuring global developmental delay. METHODS: A pregnant woman who underwent prenatal diagnosis at the Affiliated Hospital of Southwest Medical University in August 2021 was selected as the study subject. Peripheral blood samples were collected from the woman, her husband and child, in addition with amniotic fluid sample during mid-pregnancy. Genetic variants were detected by G-banded karyotyping analysis and copy number variation sequencing (CNV-seq). Pathogenicity of the variant was predicted based on the guidelines from the American College of Medical Genetics and Genomics (ACMG). Candidate variant was traced in the pedigree to assess the recurrence risk. RESULTS: The karyotypes of the pregnant woman, her fetus, and affected child were 46,XX,ins(18)(p11.2q21q22), 46,X?,rec(18)dup(18)(q21q22)ins(18)(p11.2q21q22)mat and 46,XY,rec(18)del(18)(q21q22)ins(18)(p11.2q21q22)mat, respectively. Her husband was found to have a normal karyotype. CNV-seq has revealed a 19.73 Mb duplication at 18q21.2-q22.3 in the fetus and a 19.77 Mb deletion at 18q21.2-q22.3 in her child. The duplication and deletion fragments were identical to the insertional fragment in the pregnant woman. Based on the ACMG guidelines, the duplication and deletion fragments were both predicted to be pathogenic. CONCLUSION The intrachromosomal insertion of 18q21.2-q22.3 carried by the pregnant woman had probably given rise to the 18q21.2-q22.3 duplication and deletion in the two offspring. Above finding has provided a basis for genetic counseling for this pedigree.
Child ; Female ; Humans ; Pregnancy ; DNA Copy Number Variations ; East Asian People ; Pedigree ; Prenatal Diagnosis/methods* ; Chromosomes, Human, Pair 18/genetics* ; Male ; Fetus ; INDEL Mutation

OBJECTIVE: To carry out optical genome mapping (OGM) for a Chinese pedigree with a rare paracentric reverse insertion of chromosome 17. METHODS: A high-risk pregnant woman identified at the Prenatal Diagnosis Center of Hangzhou Women's Hospital in October 2021 and her family members were selected as the study subjects. Chromosome G banding analysis, fluorescence in situ hybridization (FISH), single nucleotide polymorphism array (SNP array) and OGM were applied to verify the balanced structural abnormality of chromosome 17 in the pedigree. RESULTS: Chromosomal karyotyping analysis and SNP array assay have identified a duplication of 17q23q25 in the fetus. Karyotyping analysis of the pregnant woman showed that the structure of chromosome 17 was abnormal, whilst SNP array has detected no abnormality. OGM revealed that the woman has carried a paracentric reverse insertion, which was confirmed by FISH. The karyotype of her husband was normal. CONCLUSION The duplication of 17q23q25 in the fetus has derived from a paracentric reverse insertion of chromosome 17 in its mother. OGM has the advantage for delineating balanced chromosome structural abnormalities.
Pregnancy ; Humans ; Female ; Pedigree ; In Situ Hybridization, Fluorescence ; Chromosomes, Human, Pair 17/genetics* ; East Asian People ; Chromosome Aberrations ; Prenatal Diagnosis ; Chromosome Mapping ; Chromosome Inversion

OBJECTIVE: To explore the clinical and genetic characteristics of two children with Williams-Beuren syndrome (WBS). METHODS: Two children who had presented at the Department of Pediatrics, General Hospital of Ningxia Medical University respectively on January 26 and March 18, 2021 were selected as the study subjects. Clinical data and results of genetic testing of the two patients were analyzed. RESULTS: Both children had featured developmental delay, characteristic facies and cardiovascular malformation. Child 1 also had subclinical hypothyroidism, whilst child 2 had occurrence of epilepsy. Genetic testing revealed that child 1 has harbored a 1.54 Mb deletion in the 7q11.23 region, whilst child 2 has a 1.53 Mb deletion in the same region, in addition with a c.158G>A variant of the ATP1A1 gene and a c.12181A>G variant of the KMT2C gene. Based on the guidelines from the American College of Medical Genetics and Genomics, the c.158G>A and c.12181A>G variants were rated as variants of unknown significance (PM1+PM2_Supporting+PP2+PP3；PM2_Supporting). CONCLUSION Both children had characteristic features of WBS, for which deletions of the 7q11.23 region may be accountable. For children manifesting developmental delay, facial dysmorphism and cardiovascular malformations, the diagnosis of WBS should be suspected, and genetic testing should be recommended to confirm the diagnosis.
Child ; Humans ; Williams Syndrome/diagnosis* ; Genetic Testing ; Facies ; Epilepsy/genetics* ; Chromosomes, Human, Pair 7/genetics* ; Chromosome Deletion

OBJECTIVE: To explore the genetic etiology of two patients with developmental delay and intellectual disability. METHODS: Two children who were respectively admitted to Henan Provincial People's Hospital on August 29, 2021 and August 5, 2019 were selected as the study subjects. Clinical data were collected, and array comparative genomic hybridization (aCGH) was carried out on the children and their parents for the detection of chromosomal microduplication/microdeletions. RESULTS: Patient 1 was a 2-year-and-10-month female and patient 2 was a 3-year-old female. Both children had featured developmental delay, intellectual disability, and abnormal findings on cranial MRI. aCGH revealed that patient 1 has harbored arr[hg19] 6q14.2q15(84621837_90815662)×1, a 6.19 Mb deletion at 6q14.2q15, which encompassed ZNF292, the pathogenic gene for Autosomal dominant intellectual developmental disorder 64. Patient 2 has harbored arr[hg19] 22q13.31q13.33(46294326_51178264)×1, a 4.88 Mb deletion at 22q13.31q13.33 encompassing the SHANK3 gene, haploinsufficiency of which can lead to Phelan-McDermid syndrome. Both deletions were classified as pathogenic CNVs based on the guidelines of American College of Medical Genetics and Genomics (ACMG) and were not found in their parents. CONCLUSION The 6q14.2q15 deletion and 22q13-31q13.33 deletion probably underlay the developmental delay and intellectual disability in the two children, respectively. Haploinsufficiency of the ZNF292 gene may account for the key clinical features of the 6q14.2q15 deletion.
Humans ; Child ; Female ; Child, Preschool ; Intellectual Disability/genetics* ; Comparative Genomic Hybridization ; Chromosome Disorders/genetics* ; Chromosome Deletion ; Magnetic Resonance Imaging ; Chromosomes, Human, Pair 22 ; Developmental Disabilities/genetics* ; Carrier Proteins/genetics* ; Nerve Tissue Proteins/genetics*

OBJECTIVES: To provide a guideline for genealogy inference and family lineage investigation through a study of the mismatch tolerance distribution of Y-STR loci in Chinese Han male lineage. METHODS: Three Han lineages with clear genetic relationships were selected. YFiler Platinum PCR amplification Kit was used to obtain the typing data of 35 Y-STR loci in male samples. The variation of Y-STR haplotypes in generation inheritance and the mismatch tolerance at 1-7 kinship levels were statistically analyzed. RESULTS: Mutations in Y-STR were family-specific with different mutation loci and numbers of mutation in different lineages. Among all the mutations, 66.03% were observed on rapidly and fast mutating loci. At 1-7 kinship levels, the number of mismatch tolerance ranged from 0 to 5 on all 35 Y-STR loci, with a maximum step size of 6. On medium and slow mutant loci, the number of mismatch tolerance ranged from 0 to 2, with a maximum step size of 3; on rapidly and fast mutant loci, the number of mismatch tolerance ranged from 0 to 3, with a maximum step size of 6. CONCLUSIONS Combined use of SNP genealogy inference and Y-STR lineage investigation, both 0 and multiple mismatch tolerance need to be considered. Family lineage with 0-3 mismatch tolerance on all 35 Y-STR loci and 0-1 mismatch tolerance on medium and slow loci can be prioritized for screening. When the number of mismatch tolerance is eligible, family lineages with long steps should be carefully excluded. Meanwhile, adding fast mutant loci should also be handled with caution.
Male ; Humans ; Haplotypes ; Chromosomes, Human, Y/genetics* ; Microsatellite Repeats ; Mutation ; Asian People/genetics* ; China ; Genetics, Population

Child ; Humans ; Chromosomes, Human, Pair 16 ; Leukemia, Myeloid, Acute ; Neoplasms, Multiple Primary/genetics* ; Oncogene Proteins, Fusion/genetics* ; RNA-Binding Protein FUS/genetics* ; Sarcoma, Myeloid/genetics* ; Transcriptional Regulator ERG/genetics* ; Translocation, Genetic

OBJECTIVE: To explore the incidence of azoospermia factor c (AZFc) microdeletion among patients with azoospermia or severe oligospermia, its association with sex hormone/chromosomal karyotype, and its effect on the outcome of pregnancy following intracytoplasmic sperm injection (ICSI) treatment. METHODS: A total of 1 364 males with azoospermia or severe oligospermia who presented at the Affiliated Maternity and Child Health Care Hospital of Jiaxing College between 2013 and 2020 were subjected to AZF microdeletion and chromosome karyotyping analysis. The level of reproductive hormones in patients with AZFc deletions was compared with those of control groups A (with normal sperm indices) and B (azoospermia or severe oligospermia without AZFc microdeletion). The outcome of pregnancies for the AZFc-ICSI couples was compared with that of the control groups in regard to fertilization rate, superior embryo rate and clinical pregnancy rate. RESULTS: A total of 51 patients were found to harbor AZFc microdeletion, which yielded a detection rate of 3.74%. Seven patients also had chromosomal aberrations. Compared with control group A, patients with AZFc deletion had higher levels of PRL, FSH and LH (P < 0.05), whilst compared with control group B, only the PRL and FSH were increased (P < 0.05). Twenty two AZFc couples underwent ICSI treatment, and no significant difference was found in the rate of superior embryos and clinical pregnancy between the AZFc-ICSI couples and the control group (P > 0.05). CONCLUSION The incidence of AZFc microdeletion was 3.74% among patients with azoospermia or severe oligospermia. AZFc microdeletion was associated with chromosomal aberrations and increased levels of PRL, FSH and LH, but did not affect the clinical pregnancy rate after ICSI treatment.
Child ; Humans ; Male ; Female ; Pregnancy ; Azoospermia/genetics* ; Oligospermia/genetics* ; Incidence ; Chromosome Deletion ; Chromosomes, Human, Y/genetics* ; Semen ; Infertility, Male/genetics* ; Chromosome Aberrations ; Follicle Stimulating Hormone/genetics*

OBJECTIVE: To explore the genetic basis for a rare case of acute B-lymphocytic leukemia (B-ALL) with double Philadelphia chromosomes (Ph) and double derivative chromosome 9s [der(9)]. METHODS: A patient with double Ph and double der(9) B-ALL who presented at Shanghai Zhaxin Intergrated Traditional Chinese and Western Medicine Hospital in June 2020 was selected as the subject. Bone marrow morphology, flow cytometry, G-banding karyotyping, fluorescence in situ hybridization (FISH), genetic testing and chromosomal microarray analysis (CMA) were used to analyze bone marrow samples from the patient at various stages. RESULTS: At initial diagnosis, the patient's bone marrow morphology and flow immunotyping have both supported the diagnosis of B-ALL. G-banded karyotyping of the patient indicated double Ph, in addition with hyperdiploid chromosomes involving translocations between chromosomes 9 and 22. BCR-ABL1 fusion gene was positive. Genetic testing at the time of recurrence revealed presence of a heterozyous c.944C>T variant in the kinase region of the ABL1 gene. FISH showed a signal for ABL1-BCR fusion on both chromosome 9s. CMA showed that the mosaicism homozygosity ratio of chromosome 9 was about 40%, and the mosaicism duplication ratio of chromosome 22 was about 43%. CONCLUSION Since both der(9) homologs were seen in 40% of cells, the possible mechanism for the double der(9) in this patient may be similar to that of double Ph, which might have resulted from non-disjunction during mitosis in the Ph chromosome-positive cell clone.
Humans ; Philadelphia Chromosome ; In Situ Hybridization, Fluorescence/methods* ; China ; Chromosome Aberrations ; Precursor Cell Lymphoblastic Leukemia-Lymphoma/genetics* ; Translocation, Genetic ; Fusion Proteins, bcr-abl/genetics* ; Chromosomes, Human, Pair 9/genetics*

Spermatogenesis is regulated by several Y chromosome-specific genes located in a specific region of the long arm of the Y chromosome, the azoospermia factor region (AZF). AZF microdeletions are the main structural chromosomal abnormalities that cause male infertility. Assisted reproductive technology (ART) has been used to overcome natural fertilization barriers, allowing infertile couples to have children. However, these techniques increase the risk of vertical transmission of genetic defects. Despite widespread awareness of AZF microdeletions, the occurrence of de novo deletions and overexpression, as well as the expansion of AZF microdeletion vertical transmission, remains unknown. This review summarizes the mechanism of AZF microdeletion and the function of the candidate genes in the AZF region and their corresponding clinical phenotypes. Moreover, vertical transmission cases of AZF microdeletions, the impact of vertical inheritance on male fertility, and the prospective direction of research in this field are also outlined.
Humans ; Male ; Azoospermia/genetics* ; Sex Chromosome Aberrations ; Prospective Studies ; Chromosome Deletion ; Chromosomes, Human, Y/genetics* ; Infertility, Male/genetics* ; Sertoli Cell-Only Syndrome/genetics* ; Oligospermia/genetics*

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*