1/142. trisomy/tetrasomy 21 mosaicism in CVS: interpretation of cytogenetic discrepancies between placental and fetal chromosome complements.trisomy/tetrasomy 21 mosaicism was found in chorionic villi (semidirect preparation) obtained from a 40 year old pregnant woman. Since both cell lines were abnormal, the couple elected for pregnancy termination. placenta and fetal tissue samples were obtained for cytogenetic study. Long term cultured villi showed a non-mosaic trisomy 21 karyotype, while other tissues showed either a normal karyotype or normal/trisomy21 mosaicism. These discrepancies could be explained by a modified "bottle neck" embryogenic model with a trisomic zygote and a non-disjunction event taking place in one of the first divisions. Our case emphasises the need for confirmatory studies in other tissues when mosaicism is encountered in chorionic villi, even if all cell lines are abnormal.- - - - - - - - - - ranking = 1keywords = pregnancy (Clic here for more details about this article) |
2/142. Clinical details, cytogenic studies,and cellular physiology of a 69, XXX fetus, with comments on the biological effect of triploidy in man.A triploid fetus, 69, XXX, aborted spontaneously at 26 weeks' gestation. It had multiple abnormalities including syndactyly of the hands and feet single palmar creases, hypoplasia of the adrenals and ovaries, hypertrophy of thigh muscles, and abnormalities of the brain. The placenta was large and showed hydatidiform degeneration. The pregnancy had been complicated by acute dyspnoea, pre-eclampsia, and postpartum haemorrhage. Detailed cytogenetic studies, using banding and fluorescence techniques, were performed on fetus and parents. Meiotic studies were made on the fetal ovaries. Muscle cell differentiation and electrophysiological relationships of cultured skin fibriblasts were examined in an attempt to study the way in which the extra haploid set of chromosomes exerts its effect on the phenotype. The antenatal diagnosis of late triploidy is discussed. The finding that 25 per cent of late triploids have spina bifida is further evidence that meningomyelocele has a genetic component and strongly suggests that this results from chromosomal imbalance or a regulatory gene disturbance.- - - - - - - - - - ranking = 3.7178490596223keywords = gestation, pregnancy (Clic here for more details about this article) |
3/142. prenatal diagnosis of a mosaic extra structurally abnormal chromosome by spectral karyotyping.A de novo mosaic extra structurally abnormal chromosome (ESAC) was detected in 33 per cent of cultured amniotic fluid cells from a pregnant woman. Neither Q-banding nor fluorescence in situ hybridization (FISH) employing a dna probe for nucleolar organizer region demonstrated the presence of satellites on the ESAC. spectral karyotyping (SKY) was performed in this prenatal case and led to a quick and accurate determination of the ESAC as chromosome 14 in origin. The SKY finding was confirmed by conventional FISH analysis using a chromosome 14 specific painting probe. Subsequent hybridizations with a centromeric probe and a 14q subtelomeric probe were also performed to further characterize the ESAC. Absence of (TTAGGG)n sequence on the ESAC, determined postnatally, suggested it is a ring chromosome 14. Genetic counselling concerning these findings was provided to the parents who chose to continue the pregnancy. The male infant had no apparent abnormal phenotype at birth.- - - - - - - - - - ranking = 1keywords = pregnancy (Clic here for more details about this article) |
4/142. prenatal diagnosis in a family with severe type I plasminogen deficiency, ligneous conjunctivitis and congenital hydrocephalus.Severe type I plasminogen deficiency may cause severe ligneous conjunctivitis, a rare and unusual form of chronic pseudo-membranous conjunctivitis that usually starts in early infancy, but also pseudo-membranous lesions of other mucous membranes in the mouth, nasopharynx, trachea and female genital tract, and in rare cases congenital occlusive hydrocephalus. The index patient, the daughter of a consanguineous marriage, had suffered from severe ligneous conjunctivitis and had died from decompensated congenital hydrocephalus despite numerous shunt revisions. She was found to be homozygous for a non-sense mutation in exon 15 of the plasminogen gene (Trp597->Stop). In her next pregnancy, the mother asked for prenatal diagnosis of the plasminogen deficiency. Chorionic villus biopsy was performed at 12 weeks of gestation. dna analysis of the plasminogen gene by PCR and single-strand conformation polymorphism (SSCP) revealed that the fetus exhibited an identical heterozygous band pattern as observed in the healthy mother. Therefore, the fetus was heterozygous for the Trp597->Stop mutation in plasminogen exon 15. In addition, the fetus was found to be male by cytogenetic analysis and by multiplex PCR analysis using two polymorphic X-chromosomal markers (DXS424, HPRT). These findings excluded the possibility of contamination by maternal dna. It was concluded that the fetus was not at risk for ligneous conjunctivitis and its associated complications. After the birth of a healthy boy, plasminogen functional activity was shown to be 38 per cent. dna analysis confirmed prenatal molecular genetic results.- - - - - - - - - - ranking = 3.7178490596223keywords = gestation, pregnancy (Clic here for more details about this article) |
5/142. Partial trisomy 13q22-->qter and monosomy 18q21-->qter as a result of familial translocation.We report on a patient with a partial trisomy of chromosome 13q22-->qter and partial monosomy of chromosome 18q21-->qter showing distinct malformations. The phenotype of this unbalanced karyotype has not been previously described. The proband had a craniofacial dysmorphism, neck pterygium, closed fists with overlapping fingers, cutaneous appendix of the left fist, equinovarus and postaxial hexadactyly of the feet, atrial septum defect, unilateral cryptorchidism and hypertrophic pyloric stenosis. Using fluorescence in situ hybridization (FISH) the father's karyotype 46,XY.ish t(13;18)(13pter-->13q22::18q21-->18qter; 18pter-->18q21::13q22-->13qter) and the child's 46,XY.ish der(18)(18pter-->18q21::13q22-->13qter)pat were established. The mother's karyotype was normal. A risk of unbalanced offspring in carriers of a balanced reciprocal translocation depends on the length and genetic constitution of the exchanged segments. risk figures should come only from empirical data. A phenotypically normal child with a balanced or normal karyotype could be born in the case of alternate segregation. amniocentesis should therefore be recommended in any further pregnancy.- - - - - - - - - - ranking = 1keywords = pregnancy (Clic here for more details about this article) |
6/142. Bilateral renal agenesis and fetal ascites in association with partial trisomy 13 and partial trisomy 16 due to a 3:1 segregation of maternal reciprocal translocation t(13;16)(q12.3; p13.2).A female fetus with bilateral renal agenesis and fetal ascites was found to have partial trisomy 13 (pter-q12.3) and partial trisomy 16 (p13.2-pter), 47,XX, der(13)t(13;16)(q12.3; p13.2)mat. The chromosomal aberration was due to a 3:1 segregation with tertiary trisomy transmitted from a maternal reciprocal translocation 13;16. Prenatal ultrasound of a 29-year-old, gravida 2, para 0 woman at 22 gestational weeks showed fetal ascites, severe oligohydramnios and non-visualization of fetal urinary bladder and kidneys. The pregnancy was terminated. At delivery, the proband displayed dysmorphic features of hypertelorism, a prominent glabella, epicanthic fold, a stubby nose with a depressed nasal bridge, anteverted nares, thin lips, micrognathia, low-set ears, a short neck and a distended abdomen. Necropsy confirmed bilateral renal agenesis and ascites. A cytogenetic study performed on fibroblasts obtained from the proband's skin revealed an extra supernumerary chromosome. The mother was later found to have a reciprocal translocation. fluorescence in situ hybridization for a submicroscopic deletion in chromosome 22q11 in the proband was negative. The parents had no urological anomalies. Our observation further extends the clinical spectrum associated with proximal trisomy 13q and distal trisomy 16p. We suggest prenatal cytogenetic analysis in fetuses with urological anomalies, including renal agenesis, to uncover underlying genetic disorders.- - - - - - - - - - ranking = 3.7178490596223keywords = gestation, pregnancy (Clic here for more details about this article) |
7/142. First prenatal diagnosis of defects in the HsPDX1 gene encoding protein X, an additional lipoyl-containing subunit of the human pyruvate dehydrogenase complex.We have previously reported a genetic study of a neonatal lactic acidosis linked to a pyruvate dehydrogenase complex deficiency due to the absence of the protein X subunit. This rare autosomal recessive disorder is associated with specific deletions in this polypeptide which is encoded by the HsPDX1 gene, located on chromosome 11p1.3. The pathology of the patient was considered to arise from a large homozygous deletion (78del85) found at the 5' end of the HsPDX1 coding sequence. Her heterozygous mother underwent prenatal diagnosis during a subsequent pregnancy. Chorionic villus samples were used for three independent studies: (1) normal levels of the protein X component of the PDH complex were detected by immunoblotting; (2) RT-PCR analysis showed no deletion at the 5' end of the cDNA but the presence of a distinct heterozygous deletion (965del59) at its 3' end inherited from the father; (3) haplotype analysis revealed the presence of the father's mutated allele and the mother's normal allele. It was concluded that the fetus was heterozygous for this separate 3' deletion, so, it was likely to be not affected. This study permitted us to characterize more precisely the genetic abnormalities of the HsPDX1 cDNA occurring in each family's member.- - - - - - - - - - ranking = 1keywords = pregnancy (Clic here for more details about this article) |
8/142. Sperm quality may adversely affect the chromosome constitution of embryos that result from intracytoplasmic sperm injection.OBJECTIVE: To determine whether the high rate of chromosomal abnormalities in the embryos of an infertile couple were caused by a paternal factor that may have involved the sperm centriole. DESIGN: Case report. SETTING: Private IVF program. PATIENT(S): An infertile couple who underwent IVF-ET because of severe male factor infertility and endometriosis. INTERVENTION(S): Preimplantation genetic diagnosis of chromosomal abnormalities in embryos derived from two cycles of ICSI in which the husband's sperm was used and one in which donor sperm was used. MAIN OUTCOME MEASURE(S): Preimplantation genetic diagnosis with fluorescence in situ hybridization using probes for chromosomes X, Y, 13, 16, 18, and 21, and determination of hCG levels. RESULT(S): Most of the embryos derived from the cycles in which the husband's sperm was used were chromosomally abnormal (82%), whereas all the embryos derived from the cycle in which donor sperm was used were chromosomally normal. The cycle in which donor sperm was used resulted in an ongoing pregnancy. CONCLUSION(S): Paternal factors, which most likely derive from the centrosome, can contribute to numerical chromosomal abnormalities, which in turn may predispose to implantation failure.- - - - - - - - - - ranking = 1keywords = pregnancy (Clic here for more details about this article) |
9/142. pregnancy-exaggerated galactosemia and congenital cataracts.One child in a family and two children in another family had galactosemia and congenital cataract. Two of them had total soft cataracts while in one, cataract was less soft. In addition, they had mild lactosuria. The mothers of the affected children had significant lactosuria and mild galactosuria without cataracts. fathers did not have galactosuria or lactosuria. Clinically unaffected siblings in one family had mild galactosuria and lactosuria. pregnancy-exaggerated galactosemia was suspected in these two mothers who gave birth to children with congenital cataract. As an extension of this work, 5001 pregnant women were screened for galactose in urine just before the delivery of babies. Mild galactosuria was present in 54 (1.08%). Three children had congenital cataract and one had changes in posterior pole and cornea. Restriction of lactose by reducing intake of milk and milk products during pregnancy by mothers with galactosuria is recommended to avoid the birth of children with congenital cataract.- - - - - - - - - - ranking = 1keywords = pregnancy (Clic here for more details about this article) |
10/142. An inherited translocation t(4;15) (p16;q22) leading to two cases of partial trisomy 15.A four year old girl with severe mental retardation and multiple congenital abnormalities manifested "partial trisomy 15". Her mother, pregnant at the time of examination, possessed a balanced translocation which, after banding techniques, was identified as t(4;15)(p16;q22). Amnio-centesis revealed the karyotype of the fetus to be identical to that of the proposita and a therapeutic abortion was performed. Prenatal investigation of a subsequent pregnancy revealed a normal male karyotype. Comparison of the proposita and aborted fetus of this family with the 5 reported other cases of "partial trisomy 15" does not allow for a precise recognizable clinical syndrome.- - - - - - - - - - ranking = 1keywords = pregnancy (Clic here for more details about this article) |
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