A case of liveborn triploidy (69,XXX)

Chromosomal anomalies in the aetiology of oesophageal atresia and tracheo-oesophageal fistula

Oesophageal atresia (OA) and tracheo-oesophageal fistula (TOF) are severe congenital anomalies of which the aetiology is largely unknown. Several chromosomal anomalies have been described in patients presenting with these anatomical malformations, but until now none of these has led to the identification of a single aetiological factor. This paper reviews the chromosomal abnormalities reported in cases of OA/TOF and serves as a starting point to identify chromosomal regions harbouring genes involved in the aetiology of OA/TOF.

Parental and meiotic origin of triploidy in the embryonic and fetal periods

Triploidy is a common finding both in early spontaneous abortions and in the fetal period. Previous studies suggested that the majority of triploidy was the result of diandry, specifically dispermy. Molecular determination of parental origin in fetal triploids has shown that digyny accounts for the majority of triploids in the fetal period. The aim of this study was to determine the meiotic level at which the error leading to digynic triploidy occurs and to extend the molecular analysis of parental origin of triploidy into the embryonic period. Maternal age of digynic triploids was compared with that of the diandric cases. Using polymorphic pericentromeric markers, we have shown that the majority of digynic triploidy is the result of errors in the second meiotic division. Digyny accounted for the majority of triploids, even in the nonfetal cases. Diandry predominated in a subset of the non-fetal cases in which embryos were not present and in which the placental findings of partial hydatidiform mole (PHM) were encountered. Maternal age differed between the digynic and diandric groups only for the non-fetal cases; this was attributed to differences in ascertainment.

Placental pathology of triploidy

Triploidy is a common chromosome abnormality in spontaneous abortions. Previous studies of spontaneous abortions have suggested that approximately 85% of triploid abortuses show the placental changes of partial hydatidiform mole (PHM) and that this appearance was associated, possibly attributable, to paternal origin of the extra haploid set of chromosomes. More recent work, however, has shown that most triploidy is the result of digyny--the extra set of chromosomes originating from the mother. Given the association of PHM with diandry, these results would appear to be at odds with the results of previous studies of placental morphology in triploids. The authors reviewed the placental pathology of all cases of triploidy examined at their institution over a 2-year period and established that PHM occurs in a minority of triploid conceptuses. These results support the findings of studies showing that digyny is the most common origin of triploidy.

Flow cytometric studies in spontaneous abortions. Applications in the medico-legal practice

In the medico-legal practice differential diagnosis between spontaneous and non-spontaneous abortion is important because causes of pregnancy wastage are often obscure and, moreover, spontaneous abortion is more common than accidental or voluntary. In all the cases in which the cause of abortion is not otherwise detectable and especially in cases of discovery of fetal adnexa, it is necessary to investigate genetic causes. Recently, DNA flow cytometric analysis has been applied in determining the genetic causes of spontaneous abortions. Among karyotypic abnormalities, flow cytometric analysis on paraffin embedded material can detect only polyploidies (triploidy and tetraploidy). Trisomies, monosomies and structural anomalies cannot be detected. In our study we tried to establish whether flow cytometry could be useful in determining the genetic cause of spontaneous abortions, in the lack of any other detectable cause. Histologic examination and flow cytometric analysis were performed on a series of 395 consecutive spontaneous abortions. Histologic examination allowed the detection of a molar pattern in about 9% of cases. DNA flow cytometric analysis showed diploidy in 346 (87.59%) cases, triploidy in 37 (9.36%) cases and tetraploidy in 12 (3.03%) cases. Combined microscopic and flow cytometric analysis revealed abnormalities in 17.5% of cases. A non-diploid pattern is more frequent in molar cases (P less than 0.001). Flow cytometry seems to be interesting in forensic pathology, as it allows the detection of some frequent genetic abnormalities in dead tissues and cells, when other techniques are no longer practicable.

Radiographic findings in liveborn triploidy

The detailed radiographic features of triploidy, a fatal congenital disorder with 69 chromosomes, have not previously been reported. Radiographs of ten liveborn infants with chromosomally confirmed triploidy showed six findings highly suggestive of this diagnosis: harlequin orbits, small anterior fontanelle, gracile ribs, diaphyseal overtubulation of long bones, upswept clavicles and antimongoloid pelvis. Sixteen other less specific findings showed many similarities to those found in trisomy 18.

Morphologic anomalies in triploid liveborn fetuses

Analysis of the morphologic features of 43 complete and 11 mosaic triploid infants delivered at or after 22 weeks of gestation revealed, in addition to well-delineated gross features, a number of new or previously little emphasized histopathologic features. These included testicular Leydig cell hyperplasia, increased levels of hematopoiesis, and ovarian, adrenal, and pulmonary hypoplasia. Some of these findings appeared to be linked to partial hydatidiform mole replacing the normal placenta, which was present in about 70 per cent of the triploid cases. It is important to recognize the breadth of the triploidy spectrum, which ranges from near normalcy to multisystem involvement, and to pay special attention to the placenta. The importance of correct morphologic diagnosis of triploidy is stressed in view of the fact that its occurrence apparently does not prejudice the future reproductive performance of the parents.

Genetic studies on hydatidiform moles. I. The origin of partial moles

A study was designed to investigate the genetic origin of hydatidiform moles. Fifty-nine specimens were obtained and, on a histological basis, separated into two entities: complete and partial. The study of the genetic origin of the 15 partial moles, using cytogenetic and biochemical markers, is described. All the partial moles examined cytogenetically were triploid. One had 71 chromosomes. The sex chromosome complements of seven cases were six XXY and one XXX. Origin by dispermy was possible in seven cases and was proven in four. With the use of biochemical markers a maternal contribution was identified in three cases, and the isoenzyme pattern suggested a trisomic state for at least one locus in four cases. The mechanism of origin of partial moles was compared with spontaneously aborted and liveborn triploids. All the patients were followed up for at least 9 months, and none required treatment for persistent trophoblastic activity.

Human triploidy: association with partial hydatidiform moles and nonmolar conceptuses

A retrospective pathologic review of nearly 100 spontaneous abortions of cytogenetically verified triploid constitution revealed a majority (86 per cent) falling within the category of partial hydatidiform mole, the chief criteria being focal syncytiotrophoblastic hyperplasia, focal villous edema leading to cistern formation, scalloped outline of villi, and frequent "trophoblastic inclusion" formation. The minority (14 per cent) of the conceptuses were nonmolar with a normal or hypoplastic trophoblast. The triploid fetuses in both groups tended to die at about eight weeks' menstrual age. Intrauterine retention was generally prolonged in the partial moles, whereas nonmolar conceptuses tended to abort within the first trimester, often with live or recently dead fetuses. The problem of two distinct morphologic entities within triploidy remains to be further investigated, especially with respect to the etiologic factors responsible for the division.

Pathologic features of the eye in triploidy

Triploidy is a cytogenetic abnormality characterized by 69 chromosomes rather than the normal 46 in each cell. It is one of the most common chromosomal aberrations reported in early spontaneous abortion. Estimates are that 17-20% of chromosomally abnormal abortuses (early) are triploid. 1,2 Although the majority are stillborn, at least 25 liveborn triploidics have been reported. 3-9 All were premature and most died in the first 6 hours;the longest survival was 2 months. 4 By contrast, a diploid/triploid mosaic (mixed cell lines) individual may survive to adulthood. Although ocular lesions are one of the components of the triploidy syndrome, reports of histologic findings are comparatively rare. 1,3,6,10,11 This prompted us to study the ocular pathology in another case of triploidy. Our results confirm and extend those previously described and emphasize the pattern of ocular abnormalities in this disorder.

Ocular findings in triploidy

We studied the abnormal ocular and systemic findings in one case of true triploidy and two cases of triploid mosaicism. A liveborn triploid child 69,XXY, had abnormalities including cebocephaly, a single midline nostril, incomplete cleft palate, transverse palmar creases, partial syndactyly, and ambiguous genitalia. Ocular abnormalities included hypotelorism, blepharophimosis, microcornia, iris coloboma, cataract, persistent hyaloid vasculature, retinal dysplasia, and optic atrophy. A 16-year-old girl with triploid mosaicism had congenital left facial and body hemiatrophy, both growth and mental retardation, left-sided grand mal seizures, incontinentia pigmenti of both legs, partial syndactyly, and generalized weakness. Results of her ocular examination were within normal limits. A 13-year-old boy with triploid mosaicism exhibited both growth and mental retardation, truncal obesity, and required a brace to support his back. Ocular findings included synophrys, bilateral blepharoptosis, and abnormal results of Schirmer tear test. Studies indicate a wide spectrum of ocular and systemic abnormalities occur that are presumably associated with the chromosome error.

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.

Congenital malformations of the central nervous system in spontaneous abortions

A study of 2620 pregnancies ending in spontaneous abortion revealed a CNS defect in 3.6% of embryos and fetuses, and 3% of all complete conceptuses. The type of malformation observed varied with the gestational age at expulsion, encephaloceles being predominant in earlier specimens, while more typical anencephalus and spina bifida were more common among later abortions. Chromosome abnormalities were found in 40% of abortuses with CNS defects, but were almost entirely confined to those which were still at the embryonic stage of development. 53% of the latter were chromosomally abnormal, which is the same as the proportion found among embryos without a CNS malformation. Using published life-tables of recognized pregnancies it was estimated that the prevalence of anencephalus, spina bifida, or related malformation (other than hydrocephalus), without a chromosome anomaly, is 5.3 per thousand conceptuses at the beginning of the eighth week of gestation. By comparing this with the prevalence in total births, it was further estimated that only 24% of these are born alive, with 54% aborting spontaneously and 22% being stillborn.

Triploidy syndrome. A report on two live-born (69, XXY) and one still-born (69, XXX) infants

Two live-born cases, 69,XXY and one stillbirth, 69,XXX are reported. Further evidence is presented to delineate the triploidy syndrome. Common external and internal features which characterize the triploidy syndrome are low-set ears, hypertelorism, colobomata, syndactyly, simian creases, microphallus, undescended testes, scrotal aplasia, anomalous heart and hypoplasia of kidneys and adrenals. The triploidy syndrome encompasses features found in trisomies 13, 18 and 21. We suggest that the abnormal development of the triploidy infants is the result of the mentioned trisomies and their subsequent effect on the remaining genome.