Yen-Ni Chen

Prenatal diagnosis and molecular cytogenetic characterization of a 1.07-Mb microdeletion at 5q35.2–q35.3 associated with NSD1 haploinsufficiency and Sotos syndrome

OBJECTIVE To present prenatal diagnosis and molecular cytogenetic characterization of a de novo 5q35 microdeletion associated with Sotos syndrome. METHODS This was the first pregnancy of a 29-year-old woman. The pregnancy was uneventful until 27 weeks of gestation when left ventriculomegaly was first noted. At 31 weeks of gestation, polyhydramnios, macrocephaly, and ventriculomegaly were prominent on ultrasound, and left pyelectasis and bilateral ventriculomegaly were diagnosed on magnetic resonance imaging. The woman underwent amniocentesis and cordocentesis at 32 weeks of gestation. Conventional cytogenetic analysis was performed using cultured amniocytes and cord blood lymphocytes. Array comparative genomic hybridization (aCGH) was performed on uncultured amniocytes and parental blood. Metaphase fluorescence in situ hybridization (FISH) was performed on cultured lymphocytes. RESULTS Conventional cytogenetics revealed a karyotype of 46,XX. aCGH on uncultured amniocytes revealed a de novo 1.07-Mb microdeletion at 5q35.2-q35.3 encompassing NSD1. Metaphase FISH analysis on the cord blood lymphocytes confirmed the deletion at 5q35.2. The postnatal phenotype was consistent with Sotos syndrome. CONCLUSION Fetuses with Sotos syndrome may present macrocephaly, polyhydramnios, ventriculomegaly, and pyelectasis in the third trimester. aCGH and metaphase FISH are useful for rapid diagnosis of 5q35 microdeletion associated with Sotos syndrome.

Mosaic trisomy 15 at amniocentesis: Prenatal diagnosis, molecular genetic analysis and literature review

OBJECTIVE To present prenatal diagnosis of mosaic trisomy 15 at amniocentesis. MATERIALS AND METHODS A 37-year-old woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Cytogenetic analysis of cultured amniocytes revealed a karyotype of 47,XY,+15[2]/46,XY[17]. She was referred for repeated amniocentesis at 19 weeks of gestation. Array comparative genomic hybridization (aCGH), interphase fluorescence in situ hybridization (FISH) and quantitative fluorescent polymerase chain reaction assays on uncultured amniocytes, conventional cytogenetic analysis and aCGH on cultured amniocytes, and FISH on uncultured urinary cells after birth were applied. Cordocentesis revealed a karyotype of 46,XY. RESULTS At repeated amniocentesis, cultured amniocytes revealed a karyotypes of 46,XY [22 colonies], FISH on uncultured amniocytes revealed 21.2% (22/104 cells) mosaicism for trisomy 15, aCGH on uncultured amniocytes revealed a genomic gain (log2 ratio = 0.3) in chromosome 15, quantitative fluorescent polymerase chain reaction on uncultured amniocytes excluded uniparental disomy 15 (UPD 15), and aCGH on culture amniocytes revealed no genomic imbalance in chromosome 15. A healthy 3700 g male baby was delivered at 38 weeks of gestation with no phenotypic abnormalities at age 6 months. FISH on uncultured urinary cells at birth and at age 6 months revealed mosaic trisomy 15 levels of 20% (13/65 cells) and 12.2% (6/49 cells), respectively. CONCLUSION Prenatal diagnosis of mosaic trisomy 15 at amniocentesis should alert doctors about the occurrence of UPD 15 and a clinically significant phenotype. The present case provides evidence for cytogenetic discrepancy between uncultured and cultured amniocytes in mosaic trisomy 15 at amniocentesis. It is possible that the abnormal cell lines of amniocytes with trisomy 15 disappear after long-term cell culture.

Prenatal diagnosis and array comparative genomic hybridization characterization of interstitial deletions of 8q23.3-q24.11 and 8q24.13 associated with Langer-Giedion syndrome, Cornelia de Lange syndrome and haploinsufficiency of TRPS1, RAD21 and EXT1.

OBJECTIVE The aim of this research was to present prenatal diagnosis of Langer-Giedion syndrome (LGS/TRPS type II) and Cornelia de Lange syndrome-4 (CDLS4). MATERIALS AND METHODS A 36-year-old woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Conventional cytogenetic analysis of amniocentesis revealed an interstitial deletion of chromosome 8q or del(8)(q23.3q24.13). Level II prenatal ultrasound examination revealed craniofacial dysmorphism. The pregnancy was terminated, and a malformed fetus was delivered with characteristic craniofacial dysmorphism of LGS/TRPS type II and CDLS4. Whole-genome array comparative genomic hybridization (aCGH) on the DNA extracted from cultured amniocytes was performed. RESULTS The analysis by aCGH revealed a result of arr 8q23.3q24.11 (116,087,006-118,969,399)×1, 8q24.13 (123,086,851-124,470,847)×1 (NCBI build 37) with a 2.88-Mb deletion of 8q23.3-q24.11 encompassing six OMIM genes, TRPS1, EIF3H, RAD21, SLC30A8, MED30, and EXT1, and a 1.383-Mb deletion of 8q24.13 encompassing four OMIM genes, ZHX2, DERL1, ZHX1, and ATAD2. CONCLUSION In the present case, the conventional cytogenetic analysis of cultured amniocytes revealed del(8)(q23.3q24.13), whereas aCGH analysis of cultured amniocytes showed the deletions of 8q23.3-q24.11 and 8q24.13 with the presence of the segment 8q24.12. Therefore, aCGH provides the advantage of better understanding of the nature of interstitial deletion and genotype-phenotype correlation in this case.

Molecular cytogenetic characterization of mosaicism for a small supernumerary marker chromosome derived from chromosome 8 or r(8)(::p11.22→q11.21::) in an 18-year-old female with short stature, obesity, attention deficit hyperactivity disorder, and intellectual disability

OBJECTIVE We present molecular cytogenetic characterization of mosaicism for a small supernumerary marker chromosome (sSMC) derived from chromosome 8. MATERIALS AND METHODS An 18-year-old female presented with short stature, obesity, developmental delay, speech delay, dyslexia, attention deficit hyperactivity disorder, and intellectual disability. Cytogenetic analysis of the peripheral blood revealed a karyotype of 47,XX,+mar[22]/46,XX[18]. Array comparative genomic hybridization and metaphase fluorescence in situ hybridization analyses were performed on the peripheral blood to determine the origin and mosaicism of the sSMC, and quantitative fluorescent polymerase chain reaction was used to exclude uniparental disomy. RESULTS Array comparative genomic hybridization analysis of the blood revealed a result of arr 8p11.22q11.21 (39,136,065-49,725,726)×2.80 (Log2 ratio=0.49), consistent with 70-80% mosaicism, encompassing 33 OMIM genes including GOLGA7, AGPAT6, NKX6-3, KAT6A, and FNTA. The sSMC(8) was r(8)(::p11.22→q11.21::). Metaphase fluorescence in situ hybridization analysis using the probes of RP11-754D24 (8p11.21) and RP11-769N21 (8q11.21) showed the sSMC(8) in 12/27 of cultured lymphocytes. Quantitative fluorescent polymerase chain reaction analysis excluded uniparental disomy 8. CONCLUSION Mosaic sSMC(8) derived from r(8)(::p11.22→q11.21::) can be associated with obesity, intellectual disability, and attention deficit hyperactivity disorder.

Molecular cytogenetic characterization of mosaicism for a small supernumerary marker chromosome derived from chromosome 8 or r(8)(::p12→q13.1::) associated with phenotypic abnormalities

OBJECTIVE We present molecular cytogenetic characterization of mosaicism for a small supernumerary marker chromosome (sSMC) derived from chromosome 8. MATERIALS AND METHODS A 35-year-old woman underwent amniocentesis at 16 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 47,XY,+mar[20]/46,XY[39]. However, array comparative genomic hybridization analysis on the subcultured amniocytes revealed no genomic imbalance. Prenatal ultrasound showed bilateral ventriculomegaly, intrauterine growth restriction, and an enlarged right atrium. At 36 weeks of gestation, a 2380-g baby was delivered with mild facial dysmorphism. The baby postnatally manifested right hydronephrosis, vesicoureteral reflux, hypospadias, hypotonia, strabismus, developmental delay and mild mental retardation. Array comparative genomic hybridization and metaphase fluorescence in situ hybridization analyses were performed on the peripheral blood to determine the origin and mosaicism of the sSMC, and quantitative fluorescent polymerase chain reaction was used to exclude uniparental disomy. RESULTS The blood had a karyotype of 47,XY,+mar[17]/46,XY[23]. Array comparative genomic hybridization revealed arr 8p12q13.1 (33,476,753-67,428,722)×2.40 (Log2 ratio=0.24) encompassing 98 Online Mendelian Inheritance in Man (OMIM) genes including CHD7, consistent with 30-40% mosaicism for r(8)(::p12→q13.1::). Metaphase fluorescence in situ hybridization identified the sSMC(8) in 21/33 of cultured lymphocytes. Quantitative fluorescent polymerase chain reaction excluded uniparental disomy 8. CONCLUSION Mosaic sSMC(8) derived from r(8)(::p12→q13.1::) can present phenotypic abnormalities. Chromosome 8q12 duplication syndrome should be included in differential diagnosis when an sSMC(8) contains 8q12.2 and CHD7.

First-trimester diagnosis of recurrent omphalocele associated with fetal trisomy 18 but without parental mosaicism

a Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan b Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan c Department of Biotechnology, Asia University, Taichung, Taiwan d School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan e Institute of Clinical and Community Health Nursing, National Yang-Ming University, Taipei, Taiwan f Department of Obstetrics and Gynecology, School of Medicine, National Yang-Ming University, Taipei, Taiwan g Department of Obstetrics and Gynecology, Kaohsiung Medical University Hospital, Kaohsiung Medical University, Kaohsiung, Taiwan h Department of Bioengineering, Tatung University, Taipei, Taiwan

Pregnancy with de novo 9q34.3 microdeletion and Kleefstra syndrome in the fetus may be associated with an abnormal maternal serum screening result

a Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan b Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan c Department of Biotechnology, Asia University, Taichung, Taiwan d School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan e Institute of Clinical and Community Health Nursing, National Yang-Ming University, Taipei, Taiwan f Department of Obstetrics and Gynecology, School of Medicine, National Yang-Ming University, Taipei, Taiwan g Department of Medicine, Mackay Medical College, New Taipei City, Taiwan h Department of Pediatrics, Mackay Memorial Hospital, Taipei, Taiwan i Mackay Medicine, Nursing and Management College, Taipei, Taiwan j Department of Obstetrics and Gynecology, Chung Shan Hospital, Taipei, Taiwan k Department of Bioengineering, Tatung University, Taipei, Taiwan

Prenatal diagnosis and molecular cytogenetic characterization of de novo partial monosomy 3p (3p26.3→pter) and partial trisomy 16q (16q23.1→qter)

OBJECTIVE To present the prenatal diagnosis and molecular cytogenetic characterization of a de novo unbalanced reciprocal translocation. CASE REPORT A 37-year-old woman, G3P1, underwent amniocentesis at 17 weeks of gestation because of her advanced maternal age. Her husband was 38 years old. Amniocentesis revealed a derivative chromosome 3 with the deletion of terminal 3p and the addendum of an unknown extra chromosomal segment on the distal 3p. The parental karyotypes were normal. Prenatal ultrasound findings were unremarkable. Array comparative genomic hybridization (aCGH) analysis using cultured amniocytes revealed a 2.38-Mb deletion in 3p26.3 [arr 3p26.3 (1-2,380,760)×1] encompassing 15 genes, which included 3 OMIM genes CHL1, CNTN6, and CNTN4, and a 13.17-Mb duplication in 16q23.1-q24.3 [arr 16q23.1q24.3 (76,999,082-90,170,596)×3] encompassing 207 genes, which included 81 OMIM genes. The pregnancy was subsequently terminated, and a malformed fetus was delivered with facial dysmorphism. Postnatal cord blood analysis revealed a karyotype of 46,XY,der(3)t(3;16)(p26.3;q23.1)dn. Polymorphic DNA marker analysis by quantitative fluorescent polymerase chain reaction (QF-PCR) on the DNAs extracted from the placenta and parental blood showed a paternal origin of the aberrant chromosome. CONCLUSION The aCGH and QF-PCR analyses helped in delineating the genomic imbalance and parental origin of prenatally detected de novo unbalanced reciprocal translocation.

Prenatal diagnosis of chromosome 8p23.1 microdeletion by array comparative genomic hybridization using uncultured amniocytes in a pregnancy associated with fetal partial corpus callosum agenesis and schizencephaly

a Department of Obstetrics and Gynecology, Mackay Memorial Hospital, Taipei, Taiwan b Department of Medical Research, Mackay Memorial Hospital, Taipei, Taiwan c Department of Biotechnology, Asia University, Taichung, Taiwan d School of Chinese Medicine, College of Chinese Medicine, China Medical University, Taichung, Taiwan e Institute of Clinical and Community Health Nursing, National Yang-Ming University, Taipei, Taiwan f Department of Obstetrics and Gynecology, School of Medicine, National Yang-Ming University, Taipei, Taiwan g Taiji Fetal Medicine Center, Taipei, Taiwan h Department of Radiology, Taipei Veterans General Hospital, Taipei, Taiwan i Gene Biodesign Co. Ltd, Taipei, Taiwan j Department of Bioengineering, Tatung University, Taipei, Taiwan

Prenatal diagnosis of a familial 1q21.1-q21.2 microdeletion in a fetus with polydactyly of left foot on prenatal ultrasound

OBJECTIVE We present prenatal diagnosis of a familial 1q21.1-q21.2 microdeletion in a fetus with polydactyly of left foot on prenatal ultrasound. CASE REPORT A 30-year-old, gravida 2, para 1, woman underwent amniocentesis at 22 weeks of gestation because of fetal polydactyly of left foot and echogenic heart foci on prenatal ultrasound. She and her husband and the 2-year-old son were healthy, and there was no family history of mental disorders, skeletal abnormalities and congenital malformations. Amniocentesis revealed a karyotype of 46,XX. Simultaneous array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes revealed a 1.317-Mb 1q21.1-q21.2 microdeletion encompassing PRKAB2, FMO5, CHD1L, BCL9, ACP6, GJA5, GJA8 and GPR89B. aCGH analysis of the family members revealed that the phenotypically normal father and elder son carried the same 1q21.1-q21.2 microdeletion. The mother did not have such a deletion. The parents elected to continue the pregnancy, and a 3416-g female baby was delivered at 40 weeks of gestation with neither facial dysmorphism nor gross abnormalities except postaxial polydactyly of the left foot. CONCLUSION Fetuses with a 1q21.1-q21.2 microdeletion may present polydactyly on prenatal ultrasound, and aCGH is helpful for prenatal diagnosis under such a circumstance.