Incidental detection of familial 8p23.2 microduplication encompassing CSMD1 associated with mosaic 46,XY,t(7;8)(q31.2;p23.1)/46,XY at amniocentesis in a pregnancy with no apparent phenotypic abnormality and a favorable outcome.

OBJECTIVE: We present incidental detection of familial 8p23.2 microduplication encompassing CSMD1 associated with mosaic 46,XY,t(7;8)(q31.2;p23.1)/46,XY at amniocentesis in a pregnancy with no apparent phenotypic abnormality and a favorable outcome. CASE REPORT: A 38-year-old, gravida 2, para 1, phenotypically normal woman underwent amniocentesis at 19 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 46,XY,t(7;8)(q31.2;p23.1)[2]/46,XY[20]. The parental karyotypes were normal. Array comparative genomic hybridization (aCGH) analysis on the DNA extracted from cultured amniocytes and parental bloods revealed the result of a 2.178-Mb 8p23.2 microduplication encompassing CSMD1, or arr 8p23.2 (3,070,237-5,248,586) × 3.0 [GRCh37 (hg19)] in the fetus and the mother. The father did not have such a microduplicaiton. Prenatal ultrasound findings were unremarkable. At 38 weeks of gestation, a 2880-g phenotypically normal male baby was delivered. All the cord blood, umbilical cord and placenta had the karyotype of 46.XY. When follow-up at age six months, the neonate was normal in phenotype and development. CONCLUSION: Mosaicism for a balanced reciprocal translocation with a euploid cell line can be a transient and benign condition. Familial 8p23.2 microduplication encompassing CSMD1 can be associated with a favorable outcome.

Prenatal diagnosis and perinatal findings of 17q12 microdeletion encompassing HNF1B in a fetus with bilateral hyperechogenic kidneys on fetal ultrasound and mild renal abnormality after birth, and a review of the literature of prenatal diagnosis of 17q12 microdeletion.

OBJECTIVE: We present prenatal diagnosis and perinatal findings of 17q12 microdeletion encompassing HNF1B in a fetus with bilateral hyperechogenic kidneys on fetal ultrasound and mild renal abnormality after birth, and a review of the literature. CASE REPORT: A 36-year-old, primigravid woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Simultaneous array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes showed a de novo 1.38-Mb 17q12 microdeletion encompassing LHX1 and HNF1B. The parents did not have such a microdeletion. Prenatal ultrasound showed bilateral hyperechogenic kidneys with normal corticomedullary (CM) differentiation. The parents elected to continue the pregnancy, and a grossly normal 3180-g male baby was delivered at 39 weeks of gestation. aCGH analysis on the cord blood DNA revealed arr [GRCh37 (hg19)] 17q12 (34,856,055-36,248,918) × 1.0 with a 1.393-Mb microdeletion encompassing the genes of MYO19, PIGW, GGNBP2, DHRS11, MRM1, LHX1, AATF, ACACA, TADA2A, DUSP14, SYNRG, DDX52 and HNF1B. When follow-up at age 2 years and 4 months, the renal ultrasound revealed bilateral increased renal echogenicity with normal CM differentiation and small left renal cysts. The blood test revealed BUN = 28 mg/dL (normal: 5-18 mg/dL) and creatinine = 0.5 mg/dL (normal: 0.2-0.4 mg/dL). CONCLUSION: 17q12 microdeletion encompassing LHX1 and HNF1B at prenatal diagnosis may present variable clinical spectrum with bilateral hyperechogenic kidneys on fetal ultrasound and mild renal abnormality after birth. Prenatal diagnosis of fetal hyperechogenic kidneys should raise a suspicion of 17q12 microdeletion syndrome.

Mosaicism for a 12p12.1p12.2 microdeletion with a normal euploid cell line at amniocentesis in a pregnancy with a favorable outcome and postnatal decrease of the aneuploid cell line with microdeletion.

OBJECTIVE: We present mosaicism for a 12p12.1p12.2 microdeletion with a normal euploid cell line at amniocentesis in a pregnancy with a favorable outcome and postnatal decrease of the aneuploid cell line with microdeletion. CASE REPORT: A 35-year-old woman, gravida 2, para 1, underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed mosaic 46,XY,del (12) (p11.2p12), and array comparative genomic hybridization (aCGH) revealed arr Xp22.31 × 2 mat, 12p12.2p12.1 × 1 [0.36]dn with a 4.15-Mb 36% mosaicism for a 12p12.1p12.2 microdeletion. At 22 weeks of gestation, she underwent cord blood sampling of which aCGH revealed arr Xp22.31 × 2 mat, 12p12.2p12.1 × 1 [0.34]dn with a 4.24-Mb 34% mosaicism for a 12p12.1p12.2 microdeletion. Prenatal ultrasound findings were unremarkable. She was referred for genetic counseling, and continuing pregnancy was advised. A 2990-g male baby was delivered at 38 weeks of gestation with no phenotypic abnormality. When follow-up at age 1½ months, the neonate was phenotypically normal. The karyotype of peripheral blood was 46,XY. aCGH analysis on the DNA extracted from peripheral blood revealed the result of arr 12p12.1p12.2 (20, 367, 240-24,489,386) × 1.87, arr Xp22.31 (6,488,721-8,097,511) × 2.0 [GRCh37 (hg19)] with 10-15% (log2 ratio = 0.1) mosaicism for a 4.122-Mb 12p12.1-p12.2 microdeletion encompassing 17 OMIM genes of PDE3A, SLCO1C1, SLCO1B3, SLCO1B1, IAPP, PYROXD1, RECQL, GOLT1B, SPX, GYS2, LDHB, KCNJ8, ABCCP, CMAS, C2CD5, ETNK1 and SOX5 and a 1.609-Mb Xp22.31 duplication encompassing two OMIM genes of STS and VCX. Interphase fluorescence in situ hybridization (FISH) analysis on 104 buccal mucosal cells using 12p12.1-specific probe showed 17% (18/104 cells) mosaicism for a 12p12.1 deletion. Polymorphic DNA marker analysis on the DNA extracted from proband's blood and parental bloods determined a paternal origin of the mosaic 12p12.1 deletion. CONCLUSION: Mosaicism for a 12p12.1p12.2 microdeletion at amniocentesis with a normal euploid cell line can be a benign condition in association with a favorable fetal outcome and postnatal decrease of the aneuploid cell line with microdeletion.

Low-level mosaic trisomy 2 at amniocentesis in a pregnancy associated with positive NIPT and CVS results for trisomy 2, maternal uniparental disomy 2, perinatal progressive decrease of the aneuploid cell line, cytogenetic discrepancy between cultured amniocytes and uncultured amniocytes, intrauterine growth restriction and a favorable fetal outcome.

OBJECTIVE: We present low-level mosaic trisomy 2 at amniocentesis in a pregnancy associated with positive non-invasive prenatal testing (NIPT) and chorionic villus sampling (CVS) results for trisomy 2, maternal uniparental disomy (UPD) 2, perinatal progressive decrease of the aneuploid cell line, cytogenetic discrepancy between cultured amniocytes and uncultured amniocytes, intrauterine growth restriction (IUGR) and a favorable fetal outcome. CASE REPORT: A 35-year-old, primigravid woman underwent amniocentesis at 16 weeks of gestation because both NIPT at 9 weeks of gestation and CVS at 11 weeks of gestation revealed trisomy 2. This pregnancy was conceived by in vitro fertilization (IVF) and embryo transfer (ET). Amniocentesis revealed a karyotype of 47,XY,+2[11]/46,XY[19]. Prenatal ultrasound findings were normal. She was referred to the hospital for genetic counseling at 20 weeks of gestation, and repeat amniocentesis performed at 24 weeks of gestation revealed a karyotype of 46,XY (22/22 colonies). The parental karyotypes were normal. Quantitative fluorescent polymerase chain reaction (QF-PCR) analysis on the DNA extracted from uncultured amniocytes and parental bloods revealed maternal uniparental heterodisomy of chromosome 2. Simultaneous molecular cytogenetic analysis on uncultured amniocytes showed the results of arr 2p25.3q37.3 × 2.4 with a log2 ratio = 0.26, consistent with 40% mosaicism for trisomy 2 by array comparative genomic hybridization (aCGH), and 28% (28/100 cells) mosaicism for trisomy 2 by interphase fluorescence in situ hybridization (FISH). Despite IUGR on fetal ultrasound, the woman was advised to continue the pregnancy, and a 2252-g phenotypically normal male baby was delivered at 38 weeks of gestation. The karyotypes of cord blood, umbilical cord and placenta were 46,XY (40/40 colonies), 46,XY (40/40 colonies) and 47,XY,+2[9]/46,XY[31], respectively. QF-PCR analysis on cord blood, umbilical cord and placenta confirmed uniparental heterodisomy of chromosome 2 in the cord blood and umbilical cord, and maternal origin of trisomy 2 in the placenta. FISH analysis on buccal mucosal cells at age 1.5 months revealed 8.7% (9/104 cells) mosaicism for trisomy 2. When follow-up at age four months, the neonate manifested a normal phenotype except intermittent hypoventilation. Molecular analysis of the PHOX2B gene revealed a normal result. When follow-up at age one year, he manifested normal development. CONCLUSION: Mosaic trisomy 2 at prenatal diagnosis should alert the possibility of UPD 2 and include a UPD 2 testing. Low-level mosaic trisomy 2 at amniocentesis can be associated with perinatal progressive decrease of the aneuploid cell line and a favorable fetal outcome.

Low-level mosaic trisomy 21 at amniocentesis in a pregnancy associated with a negative NIPT result, cytogenetic discrepancy in various tissues, perinatal progressive decrease of the aneuploid cell line and a favorable fetal outcome.

OBJECTIVE: We present low-level mosaic trisomy 21 at amniocentesis associated with a favorable fetal outcome. CASE REPORT: A 31-year-old primigravid woman underwent non-invasive prenatal testing (NIPT) at 12 weeks of gestation, and the result was normal. She underwent amniocentesis at 16 weeks of gestation because of fetal choroid plexus cyst, and the result was 47,XX,+21[5]/46,XX[32]. Repeat amniocentesis was performed at 19 weeks of gestation, and the result was 47,XX,+21[5]/46,XX[15]. Simultaneous array comparative genomic hybridization (aCGH) analysis on uncultured amniocytes revealed the result of arr (21) × 3 [0.10], consistent with 10% mosaicism for trisomy 21. Prenatal ultrasound findings were unremarkable. She was referred for genetic counseling at 22 weeks of gestation, and the third amniocentesis was performed at 25 weeks of gestation, and the result was 46,XX (20/20 colonies). The parental karyotypes were normal. Simultaneous quantitative fluorescence polymerase chain reaction (QF-PCR) analysis on the DNA extracted from uncultured amniocytes and parental bloods excluded uniparental disomy (UPD) 21. aCGH analysis on uncultured amniocytes revealed arr 21q11.2q22.3 × 2.1 (log2 ratio = 0.1), consistent with 10-15% mosaicism for trisomy 21. Fluorescence in situ hybridization (FISH) analysis on uncultured amniocytes revealed 30% (30/100 cells) mosaicism for trisomy 21. The woman was advised to continue the pregnancy, and a phenotypically normal 2800-g female baby was delivered at 38 weeks of gestation. The karyotype of cord blood, umbilical cord and placenta were 47,XX,+21[1]/46,XX[39]. 47,XX,+21[4]/46,XX[36] and 46,XX (40/40 cells), respectively. When follow-up at age two months, the neonate was phenotypically normal. The peripheral blood had a karyotype of 47,XX,+21[1]/46,XX[39], and FISH analysis on buccal mucosal cells revealed 8.4% (7/83 cells) mosaicism for trisomy 21, compared with 0% in the normal control. CONCLUSION: Low-level mosaic trisomy 21 at amniocentesis can be associated with a negative NIPT result, cytogenetic discrepancy in various tissues, perinatal progressive decrease of the aneuploid cell line and a favorable fetal outcome.

Prenatal diagnosis and molecular cytogenetic characterization of a de novo deletion of 4q34.1→qter associated with low PAPP-A and low PlGF in the first-trimester maternal serum screening, congenital heart defect on fetal ultrasound and a false negative non-invasive prenatal testing (NIPT) result.

OBJECTIVE: We present prenatal diagnosis and molecular cytogenetic characterization of a de novo deletion of 4q34.1→qter associated with low pregnancy associated plasma protein-A (PAPP-A) and low placental growth factor (PlGF) in the first-trimester maternal serum screening, congenital heart defect (CHD) on fetal ultrasound and a false negative non-invasive prenatal testing (NIPT) result. CASE REPORT: A 40-year-old, primigravid woman underwent amniocentesis at 20 weeks of gestation because of advanced maternal age. This pregnancy was conceived by in vitro fertilization (IVF) and embryo transfer (ET). First-trimester maternal serum screening at 12 weeks of gestation revealed low PAPP-A [0.349 multiples of the median (MoM)] and low PlGF (0.299 MoM) and showed a risk for fetal trisomy 21 and trisomy 13. However, NIPT detected no genomic imbalance and a normal result. Nevertheless, level II ultrasound revealed ventricular septal defect, single umbilical artery and a small brain midline cyst. Amniocentesis revealed a karyotype of 46,XX,del(4)(q34.1) and a 17.8-Mb deletion of 4q34.1q.35.2 on array comparative genomic hybridization (aCGH) analysis. The parental karyotypes were normal. The pregnancy was terminated at 23 weeks of gestation, and a malformed fetus was delivered with craniofacial dysmorphism. Postnatal cytogenetic analysis of the placenta confirmed the prenatal diagnosis. There was a 17.8-Mb deletion of 4q34.1q.35.2 encompassing the genes of HAND2, SORBS2 and DUX4. Polymorphic DNA marker analysis on the parental bloods and cord blood showed a paternal origin of the deletion. CONCLUSION: An abnormal first-trimester maternal serum screening result along with abnormal fetal ultrasound should alert the possibility of fetal aneuploidy, and amniocentesis is indicated even in the presence of a normal NIPT result.

Prenatal diagnosis of partial monosomy 8p (8p23.2→pter) and partial trisomy 15q (15q21.2→qter) and incidental detection of a familial chromosome translocation of paternal origin in a pregnancy associated with increased nuchal translucency and an abnormal maternal serum screening result.

OBJECTIVE: We present partial monosomy 8p (8p23.2→pter) and partial trisomy 15q (15q21.2→qter) and incidental detection of a familial chromosome translocation of paternal origin in a pregnancy associated with increased nuchal translucency (NT) and an abnormal maternal serum screening result. CASE REPORT: A 29-year-old primigravid woman underwent chorionic villus sampling (CVS) at 13 weeks of gestation because of an increased NT thickness of 3.2 mm at 12 weeks of gestation and an abnormal maternal serum screening for Down syndrome result with a calculated risk of 1/29. Her husband was 33 years old, and there was no family history of congenital malformations. CVS revealed a derived chromosome 8 or der(8). Cytogenetic analysis of the parents revealed a karyotype of 46,XY,t(8;15)(p21.3;q13) in the father and a karyotype of 46,XX in the mother. The CVS result was 46,XY,der(8)t(8;15)(p21.3;q13)pat. The woman requested for amniocentesis at 16 weeks of gestation. Array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes revealed a result of arr 8p23.3p23.2 (191,530-2,625,470) × 1.0, arr 15q21.2q26.3 (50,903,432-102,338,129) × 3.0 with a 2.434-Mb deletion of 8p23.3-p23.2 including DLGAP2, CLN8 and ARHGEF10, and a 51.435-Mb duplication of 15q21.2-q26.3 including CYP19A1 and IGF1R. Conventional cytogenetic analysis of cultured amniocytes revealed the result of 46,XY,der(8) t(8;15)(p23.2;q21.2)pat in the fetus. The pregnancy was subsequently terminated, and a malformed fetus was delivered with characteristic craniofacial dysmorphism. CONCLUSION: Maternal serum screening and NT screening may incidentally detect familial unbalanced reciprocal translocations, and aCGH analysis is useful for a precise determination of the breakpoints of the translocation and the involvement of the related genes under such a circumstance.

Prenatal diagnosis and molecular cytogenetic characterization of mosaicism for a small supernumerary marker chromosome derived from 2q11.1-q12.1 associated with fetal bilateral radial dysplasia.

OBJECTIVE: We present prenatal diagnosis and molecular cytogenetic characterization of mosaicism for a small supernumerary marker chromosome (sSMC) derived from 2q11.1-q12.1 associated with fetal bilateral radial dysplasia. CASE REPORT: A 27-year-old woman underwent amniocentesis at 18 weeks of gestation because of club hands on fetal ultrasound. The internal organs of the fetus were normal. Amniocentesis revealed a karyotype of 47,XY,+mar [13]/46,XY [11]. The parental karyotypes were normal. Simultaneous array comparative genomic hybridization (aCGH) analysis of the DNA extracted from uncultured amniocytes revealed the result of arr 2q11.1q12.1 (95,529,039-102,825,556) × 3.0 [GRCh37 (hg19)]. The pregnancy was terminated at 20 weeks of gestation, and a malformed fetus was delivered with isolated bilateral radial dysplasia. The cord blood had a karyotype of 47,XY,+mar[24]/46,XY[16]. Polymorphic DNA marker analysis of the DNAs extracted from umbilical cord and parental bloods excluded uniparental disomy for chromosome 2. Metaphase fluorescence in situ hybridization analysis confirmed an sSMC derived from chromosome 2q11.1-q12.1 in cultured amniocytes. CONCLUSION: High-level mosaicism for an sSMC derived from chromosome 2q11.1-q12.1 can be associated with fetal abnormalities.

Prenatal diagnosis of maternal uniparental disomy 5 by amniocentesis associated with confined placental mosaicism for trisomy 5 and fetal trisomy 21 in a pregnancy.

OBJECTIVE: We present prenatal diagnosis of maternal uniparental disomy (UPD) 5 by amniocentesis associated with confined placental mosaicism (CPM) for trisomy 5 and fetal trisomy 21 in a pregnancy. CASE REPORT: A 45-year-old woman underwent chorionic villus sampling (CVS) at 11 weeks of gestation because of maternal advanced age and an increased nuchal translucency of 4.0 mm in the first-trimester screening. CVS revealed a karyotype of 47,XY,+21[98]/48,XY,+5,+21[25]. Array comparative genomic hybridization (aCGH) analysis on the DNA extracted from chorionic villi revealed arr (5) × 3, arr (21) × 3 compatible with double trisomy 5 and trisomy 21. The woman underwent amniocenteses at 20 weeks and 22 weeks of gestation. Amniocenteses revealed a karyotype of 47,XY,+21. The parental karyotypes were normal. Quantitative fluorescent polymerase chain reaction (QF-PCR) on the DNA extracted from uncultured amniocytes showed trisomy 21 of maternal origin and maternal UPD 5. aCGH and interphase fluorescence in situ hybridization (FISH) on uncultured amniocytes confirmed trisomy 21. Prenatal ultrasound findings were unremarkable. The parents decided to continue the pregnancy, and a 2,198-g male baby was delivered at 38 weeks of gestation with characteristic phenotype of Down syndrome of hypertelorism, epicanthic folds and hypoplastic middle phalanx of the fifth fingers. Cytogenetic analysis of cord blood, umbilical cord and placenta revealed a karyotype of 47,XY,+21. QF-PCR analysis of the DNA extracted from placenta revealed double trisomy 5 and trisomy 21 with maternal gene dosage increase in chromosome 5 and chromosome 21. CONCLUSION: Prenatal diagnosis of CPM for trisomy 5 at CVS can be associated with UPD 5 in the fetus, and UPD 5 causes no specific phenotype.

Prenatal diagnosis of low-level mosaicism for trisomy 21 by amniocentesis in a pregnancy associated with maternal uniparental disomy of chromosome 21 in the fetus and a favorable outcome.

OBJECTIVE: We present perinatal molecular cytogenetic analysis of low-level mosaicism for trisomy 21 in a pregnancy with maternal uniparental disomy (UPD) of chromosome 21 in the fetus. CASE REPORT: A 39-year-old woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 47,XX,+21[6]/46,XX[25]. Simultaneous array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes revealed arr (21) × 2-3, (X) × 2 with about 18% gene dosage increase in chromosome 21 consistent with mosaic trisomy 21. Cordocentesis was performed at 20 weeks of gestation, and the cord blood lymphocytes had a karyotype of 47,XX,+21[3]/46,XX[72]. Prenatal ultrasound findings were unremarkable. After genetic counseling, the parents decided to continue the pregnancy. At 39 weeks of gestation, a 3,494-g phenotypically normal female baby was delivered without phenotypic features of Down syndrome. There was no dysplasia of middle phalanx of the fifth fingers of both hands. The cord blood had a karyotype of 47,XX,+21[2]/46,XX[48]. The placenta had a karyotype of 47,XX,+21[37]/46,XX[3]. The umbilical cord had a karyotype of 47,XX,+21[1]/46,XX[39]. aCGH analysis on the DNA extracted from cord blood revealed no genomic imbalance. Polymorphic DNA marker analysis on the DNAs extracted from cord blood and parental bloods revealed maternal uniparental heterodisomy 21 in the baby. Interphase fluorescence in situ hybridization analysis on buccal mucosal cells revealed trisomy 21 signals in 15/101 (14.9%) buccal cells at birth and in 1/122 (0.82%) buccal cells at age 45 days. CONCLUSION: Low-level mosaicism for trisomy 21 at amniocentesis associated with maternal UPD 21 in the fetus can have a favorable outcome.

Detection of a familial 1q21.1 microdeletion and concomitant CHD1L mutation in a fetus with oligohydramnios and bilateral renal dysplasia on prenatal ultrasound.

OBJECTIVE: We present detection of a familial 1q21.1 microdeletion and concomitant CHD1L mutation in a fetus with oligohydramnios and bilateral renal dysplasia on prenatal ultrasound. CASE REPORT: A 37-year-old, primigravid woman was referred for level II ultrasound examination at 16 weeks of gestation because of oligohydramnios. The parents were phenotypically normal, and there were no congenital malformations in the family. Prenatal ultrasound at 17 weeks of gestation revealed a fetus with fetal growth biometry equivalent to 16 weeks, oligohydramnios with an amniotic fluid index (AFI) of 1.4 cm and bilateral renal dysplasia without sonographic demonstration of bilateral renal arteries. The pregnancy was subsequently terminated, and a 137-g fetus was delivered without characteristic facial dysmorphism. Postnatal cytogenetic analysis of the umbilical cord and parental bloods revealed normal karyotypes. However, array comparative genomic hybridization (aCGH) analysis on the DNA extracted from the umbilical cord revealed a 2.038-Mb microdeletion of 1q21.1-q21.2 encompassing 11 [Online Mendelian Inheritance in Man (OMIM)] genes of PRKAB2, FMO5, CHD1L, BCL9, ACP6, GJA5, GJA8, GPR89B, NBPF14, TRN-GTT2-1 and NBPF20. The mother was found to carry the same microdeletion. A missense mutation of c.2353T > G, p.Ser785Ala in CHD1L was detected in the umbilical cord. The father was found to carry a heterozygous mutation of c.2353T > G, p.Ser785Ala in CHD1L. CONCLUSION: Fetuses with a 1q21.1 microdeletion and concomitant CHD1L mutation may present oligohydramnios and bilateral renal dysplasia on prenatal ultrasound.

Detection of a familial 21q22.3 microduplication in a fetus associated with congenital heart defects.

OBJECTIVE: We present a familial 21q22.3 microduplication in a fetus associated with prenatally detected congenital heart defects (CHD). CASE REPORT: A 38-year-old woman underwent amniocentesis at 22 weeks of gestation because of sonographic findings of double outlet of right ventricle, ventricular septal defect and transposition of great artery in the fetus. Her husband was 42 years old, and there was no CHD and congenital malformation in the family. Cytogenetic analysis revealed a karyotype of 46,XY in the fetus. Simultaneous array comparative genomic hybridization (aCGH) analysis using uncultured amniocytes revealed a 0.56-Mb microduplication of 21q22.3 or arr 21q22.3 (47,482,210-48,043,704)×3.0 [GRCh37 (hg19)] encompassing nine Online Mendelian Inheritance in Man (OMIM) genes of FTCD, SPATC1L, LSS, MCM3AP, YBEY, PCNT, DIP2A, S100B and PRMT2. aCGH analysis of the parental bloods revealed that the phenotypically normal father carried the same microduplication. The parents decided to continue the pregnancy, and a 3168-g male baby was delivered at term without Down syndrome phenotype except CHD. Mutational analysis of the CRELD1 gene on the DNA extracted from the cord blood showed no mutation in CRELD1. Postnatal molecular cytogenetic analysis of the cord blood confirmed the prenatal diagnosis. The infant underwent a successful heart surgery to correct the CHD and was doing well without psychomotor or developmental delay at six months of age. CONCLUSION: Prenatal diagnosis of 21q22.3 microduplication associated with CHD should include a differential diagnosis of Down syndrome.

Prenatal diagnosis of a familial 5p14.3-p14.1 deletion encompassing CDH18, CDH12, PMCHL1, PRDM9 and CDH10 in a fetus with congenital heart disease on prenatal ultrasound.

OBJECTIVE: We present prenatal diagnosis of a familial 5p14.3-p14.1 deletion in a fetus with congenital heart disease on prenatal ultrasound. CASE REPORT: A 33-year-old woman underwent amniocentesis at 18 weeks of gestation because of fetal ventricular septal defect (VSD) and echogenic bowel on prenatal ultrasound. Amniocentesis revealed a karyotype of 46,XX,del (5) (p14p14). Simultaneous array comparative genomic hybridization (aCGH) analysis on the DNA extracted from uncultured amniocytes revealed a 5.589-Mb 5p14.3-p14.1 deletion or arr 5p14.3p14.1 (19, 497, 649-25,086,268) × 1.0 [GRCh37 (hg19)] encompassing CDH18, CDH12, PMCHL1, PRDM9 and CDH10. Cytogenetic and aCGH analyses of the parents showed that the phenotypically normal mother carried the 5p14.3-p14.1 deletion. The father did not have such a deletion. The parents elected to continue the pregnancy, and a 3426-g female baby was delivered at 38 weeks of gestation with no gross abnormalities. The infant postnatally manifested VSD, atrial septal defect and patent ductus areriosus, and underwent cardiac surgery to treat the congenital heart disease. When follow-up at age 1 year and 4 months, she had a body weight of 8.8 Kg (50th-75th centile), a body height of 75.6 cm (85th-95th centile) and normal psychomotor development. CONCLUSION: Fetuses with a 5p14.3-p14.1 deletion may present congenital heart disease on prenatal ultrasound, and aCGH is helpful for prenatal diagnosis under such a circumstance.

Prenatal diagnosis of a 0.7-Mb 17p13.3 microdeletion encompassing YWHAE and CRK but not PAFAH1B1 in a fetus without ultrasound abnormalities.

OBJECTIVE: We present prenatal diagnosis and molecular cytogenetic characterization of 17p13.3 microdeletion encompassing YWHAE and CRK but not PAFAH1B1 in a fetus without ultrasound abnormalities. CASE REPORT: A 33-year-old woman underwent amniocentesis at 17 weeks of gestation because of a family history of spinocerebellar atrophy in the husband. Amniocentesis revealed a karyotype of 46,XX. Simultaneously array comparative genomic hybridization (aCGH) analysis (using 60,000 probes) revealed a 0.7-Mb 17p13.3 microdeletion or arr 17p13.3 (1,264,243-1,965,733) × 1 dn [GRCh37 (hg19)] encompassing YWHAE and CRK but not PAFAH1B1. Prenatal ultrasound findings were unremarkable. There were no structural abnormalities of the brain, heart, kidneys, skull, limbs and other internal organs. The parents elected to terminate the pregnancy, and a 268-g fetus was delivered at 19 weeks of gestation with mild facial dysmorphism. Postnatal high-resolution aCGH analysis of the placenta (using 630,000 probes) showed a 0.79-Mb 17p13.3 microdeletion or arr 17p13.3 (1,173,549-1,970,690) × 1 (hg19) encompassing TUSC5, YWHAE, CRK and HIC1 but not PAFAH1B1. Metaphase fluorescence in situ hybridization analysis using the 17p13.3-specific probe of RP11-818O24 revealed a 17p13.3 deletion. CONCLUSION: Fetus with 17p13.3 microdeletion without involving PAFAH1B1 may present no brain abnormalities on fetal ultra sound.

Molecular cytogenetic characterization of a duplication of 15q24.2-q26.2 associated with anencephaly and neural tube defect.

OBJECTIVE: We present molecular cytogenetic characterization of a duplication of 15q24.2-q26.2 associated with anencephaly and neural tube defect (NTD). CASE REPORT: A 35-year-old pregnant woman was found to have a fetus with anencephaly by prenatal ultrasound at 12 weeks of gestation. The pregnancy was subsequently terminated, and a malformed fetus was delivered with anencephaly. Cytogenetic analysis of the cultured placental tissues revealed a karyotype of 46,XX,dup(15) (q24.2q26.2). Parental karyotypes were normal. Array comparative genomic hybridization analysis of the placental tissues revealed a 20.36-Mb duplication of 15q24.2-q26.2 encompassing 100 Online Mendelian Inheritance of in Man (OMIM) genes including LINGO1, MTHFS, KIF7 and CHD2. Metaphase fluorescence in situ hybridization analysis using 15q25.1-specidic probe confirmed a duplication of 15q25.1. Polymorphic DNA marker analysis showed a maternal origin of the duplication. CONCLUSION: A duplication of chromosome 15q24.2-q26.2 can be associated with NTD.

Prenatal diagnosis and molecular cytogenetic characterization of mosaicism for a small supernumerary marker chromosome derived from chromosome 21q11.2-q21.1 and a literature review.

OBJECTIVE: We present prenatal diagnosis and molecular cytogenetic characterization of mosaicism for a small supernumerary marker chromosome (sSMC) derived from chromosome 21q11.2-q21.1, and we review the literature of an sSMC(21) with a duplication of 21q11.2-q21.1. CASE REPORT: A 40-year-old woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 47,XX,+mar [18]/46,XX [4]. The parental karyotypes were normal. Prenatal ultrasound findings were unremarkable. aCGH analysis of cultured amniocytes revealed a 2.855-Mb duplication of 21q11.2-q21.1 encompassing the genes of LIPI, ABCC13 and NRIP1. Metaphase fluorescence in situ hybridization analysis on cultured amniocytes revealed a result of 47,XX,+mar .ish der(13/21) (D13/21Z1+) [10]. Spectral karyotyping analysis determined the origin of chromosome 21 in the sSMC. A female fetus was delivered with no phenotypic features of Down syndrome and no structural abnormalities. We discuss the genotype-phenotype correlation of LIPI, ABCC13 and NRIP1, and review the literature of an sSMC(21) associated with dup(21)(q11.2q21.1). CONCLUSION: aCGH is useful for identification of the nature and genetic component of a prenatally detected sSMC.

Molecular genetic characterization of a prenatally detected de novo interstitial deletion of chromosome 20p (20p12-p13) encompassing JAG1 and a literature review of prenatal diagnosis of Alagille syndrome.

OBJECTIVE: We present prenatal diagnosis and molecular genetic characterization of a de novo interstitial deletion of chromosome 20p (20p12-p13) and a literature review of prenatal diagnosis of Alagille syndrome (ALGS). CASE REPORT: A 33-year-old woman underwent amniocentesis at 17 weeks of gestation because of an abnormal result of combined first-trimester screening. Her husband was 35 years old, and there was no family history of congenital malformations. Amniocentesis revealed a karyotype of 46,XY,del(20)(p12p13), and array comparative genomic hybridization analysis on uncultured amniocytes revealed a 3.749-Mb deletion at 20p13-p12.3 and a 1.84-Mb deletion at 20p12.2 encompassing the gene of JAG1. The parental karyotypes were normal. Prenatal ultrasound findings were unremarkable. The fetus postnatally manifested characteristic facial features of ALGS. Postnatal molecular cytogenetic analysis of fetal tissues confirmed the prenatal diagnosis. Polymorphic DNA marker analysis revealed a paternal origin of the deletion. CONCLUSION: A de novo interstitial 20p deletion can be caused by a paternal effect. Pregnancy with a fetus affected with ALGS may be associated with an abnormal result of combined first-trimester screening and manifest no detectable ultrasound abnormalities.

Detection of mosaic 15q11.1-q11.2 deletion encompassing NBEAP1 and POTEB in a fetus with diffuse lymphangiomatosis.

OBJECTIVE: We present cytogenetic and molecular cytogenetic diagnoses of mosaic deletion of chromosome 15q11.1-q11.2 in a fetus with diffuse lymphangiomatosis. CASE REPORT: A 33-year-old woman underwent amniocentesis at 22 weeks of gestation because of fetal diffuse lymphangiomatosis involving left-side chest, abdominal cavity, thigh and vulva, and intrauterine growth restriction. Amniocentesis revealed a karyotype of 46,XX,del(15) (q11.1q11.2)[9]/46,XX[26]. The mother had a karyotype of 46,XX. The father had a karyotype of 46,XY. The parents elected to terminate the pregnancy. A 610-g female fetus was delivered at 23 weeks of gestation with large cystic lymphangioma over the left abdomen, thigh, and vulva. The umbilical cord had a karyotype of 46,XX,del(15)(q11.1q11.2)[24]/ 46,XX[16]. The placental tissue had a karyotype of 46,XX,del(15)(q11.1q11.2)[23]/ 46,XX[17]. Array comparative genomic hybridization analysis of the umbilical cord and placenta revealed a 2.42-Mb deletion of 15q11.1-q11.2 encompassing the genes of NBEAP1 and POTEB. CONCLUSION: Deletion of 15q11.1-q11.2 encompassing NBEAP1 and POTEB may be associated with diffuse lymphangiomatosis.

Prenatal diagnosis of partial monosomy 5p (5p15.1→pter) and partial trisomy 7p (7p15.2→pter) associated with cystic hygroma, abnormal skull development, and ventriculomegaly.

OBJECTIVE: Prenatal diagnosis of concomitant chromosome 5p deletion syndrome and chromosome 7p duplication syndrome in a fetus with abnormal prenatal ultrasound is presented. CASE REPORT: A 34-year-old woman was referred for amniocentesis at 22 weeks of gestation because of an irregular-shaped skull, bilateral ventriculomegaly, and nuchal cystic hygroma. Amniocentesis revealed a derivative chromosome 5 with a distal 5p deletion and an addendum of an extra unknown chromosomal segment at the breakpoint of 5p. Cytogenetic analysis of parental bloods revealed a karyotype of 46, XX, t(5;7)(p15.1;p15.2) in the mother and a karyotype of 46,XY in the father. The karyotype of the fetus was 46, XX, der(5) t(5;7)(p15.1;p15.2)mat consistent with partial monosomy 5p (5p15.1→pter) and partial trisomy 7p (7p15.2→pter). A malformed fetus was subsequently delivered with an irregular-shaped skull, a large anterior fontanelle, brachycephaly, hypertelorism, a high and prominent forehead, a large nuchal cystic hygroma, large low-set ears, a short and flattened nose, and micrognathia. Array comparative genomic hybridization analysis of the placenta revealed the result of arr 5p15.33p15.1 (22,179-18,133,327)×1.0, 7p22.3p15.2 (54,215-25,551,540)×3.0, indicating an 18.11-Mb deletion of 5p (5p15.33-p15.1) and a 22.5-Mb duplication of 7p (7p22.3-p15.2). Cord blood sampling revealed a karyotype of 46, XX, der(5)t(5;7) (p15.1;p15.2)mat. CONCLUSION: Fetuses with 5p deletion syndrome and 7p duplication syndrome may present ventriculomegaly, abnormal skull development, and cystic hygroma on prenatal ultrasound.