Origin Of Triploidy Research Articles

The Contribution of QF-PCR and Pathology Studies in the Diagnosis of Diandric Triploidy/Partial Mole.

Objective: the aim of our study was to assess the contribution of quantitative fluorescent polymerase chain reaction (QF-PCR) and pathology studies in the diagnosis of diandric triploidies/partial hydatidiform moles. Methods: this study included all fet al triploidies diagnosed by QF-PCR in chorionic villi or amniotic fluid in the 2 centers of BCNatal in which a maternal saliva sample was used to establish its parental origin. Pathology studies were performed in products of conception and concordance between a partial hydatidiform mole diagnosis and the finding of a diandric triploidy was assessed. Results: among 46 fetal triploidies, found in 13 ongoing pregnancies and in 33 miscarriages, there were 26 (56%) diandric triploidies. Concordant molecular (diandric triploidy) and pathology results (partial mole) were achieved in 14 cases (54%), while in 6 cases (23%) pathology studies were normal, and in the remaining 6 cases (23%) pathology studies could not be performed because miscarriage was managed medically. Conclusions: diandric triploidy is associated with partial hydatidiform mole and its diagnosis is crucial to prevent the development of persistent trophoblastic disease. QF-PCR analysis in chorionic villi or amniotic fluid provides a more accurate diagnosis of the parental origin of triploidy than the classical pathology studies.

Distribution of diandric and digynic triploidy depending on gestational age

PurposeTo establish the distribution of diandric and digynic triploidy depending on gestational age.Methods107 triploid samples tested prospectively in a single genetic department during a four-year period were analyzed for parental origin of triploidy by Quantitative Fluorescent Polymerase Chain Reaction (QF-PCR) (n=95) with the use of matching parental samples or by MS-MLPA (n=12), when parental samples were unavailable. Tested pregnancies were divided into three subgroups with regard to the gestational age at spontaneous pregnancy loss: <11 gestational weeks, 11–14 gestational weeks, and >14 gestational weeks.ResultsDiandric triploidy constituted overall 44.9% (46.5% in samples miscarried <11 gestational weeks, 64.3% in samples miscarried between 11 and 14 gestational weeks, and 27.8% in pregnancies which survived >14 gestational weeks).ConclusionsThe distribution of diandric and digynic triploidy depends on gestational age. The majority of diandric triploid pregnancies is lost in the first trimester of pregnancy. In the second trimester, diandric cases are at least twice less frequent than digynic ones.

Molecular and histological characteristics of early triploid and partial molar pregnancies

Molar pregnancy has the highest incidence of all gestational trophoblastic diseases. This is a heterogeneous group of diseases, composed of precancerous lesions and gestational trophoblastic tumours. The hydatidiform mole is characterised by varying degrees of proliferation of syncytiotrophoblastic and cytotrophoblastic cells and stromal oedema. Based on established morphological and cytogenetic criteria, molar pregnancy is divided into partial and complete. The risk of persistent trophoblastic disease is higher in complete moles compared with partial moles. The aim of this study was to assess the importance of additional molecular methods as a conjunction to the standard histopathological analysis to accurately determine the type and origin of triploidy and to detect partial molar pregnancy. This study examined a total of 24 cases of triploidy. Apart from the detailed histomorphological analysis, a molecular analysis of the placental tissue and maternal DNA was also performed. Digynic triploidy was found in 15 cases, whereas diandric triploidy was found in nine of the cases. The results showed that due to the histomorphological overlap between partial molar pregnancy and hydropic abortions, concomitant histopathological analysis of the placental tissue and molecular analysis of the placental and maternal DNA can lead to correct diagnosis.

Origin of triploidy in human abortuses

HereditasVolume 71, Issue 1 p. 168-171 Open Access Origin of triploidy in human abortuses Jon Jonasson, Jon Jonasson Department of Clinical Genetics, Karolinska Hospital, Stockholm, Sweden; Institute of Human Genetics, University of Aarhus, Aarhus, Denmark; Department of Surgery, Aarhus County Hospital, Aarhus, Denmark.Search for more papers by this authorÅge J. Therkelsen, Corresponding Author Åge J. Therkelsen Department of Clinical Genetics, Karolinska Hospital, Stockholm, Sweden; Institute of Human Genetics, University of Aarhus, Aarhus, Denmark; Department of Surgery, Aarhus County Hospital, Aarhus, Denmark.Institute of Human Genetics University of Aarhus DK-8000 Aarhus C, DenmarkSearch for more papers by this authorJørgen Glenn Lauritsen, Jørgen Glenn Lauritsen Department of Clinical Genetics, Karolinska Hospital, Stockholm, Sweden; Institute of Human Genetics, University of Aarhus, Aarhus, Denmark; Department of Surgery, Aarhus County Hospital, Aarhus, Denmark.Search for more papers by this authorJan Lindsten, Jan Lindsten Department of Clinical Genetics, Karolinska Hospital, Stockholm, Sweden; Institute of Human Genetics, University of Aarhus, Aarhus, Denmark; Department of Surgery, Aarhus County Hospital, Aarhus, Denmark.Search for more papers by this author Jon Jonasson, Jon Jonasson Department of Clinical Genetics, Karolinska Hospital, Stockholm, Sweden; Institute of Human Genetics, University of Aarhus, Aarhus, Denmark; Department of Surgery, Aarhus County Hospital, Aarhus, Denmark.Search for more papers by this authorÅge J. Therkelsen, Corresponding Author Åge J. Therkelsen Department of Clinical Genetics, Karolinska Hospital, Stockholm, Sweden; Institute of Human Genetics, University of Aarhus, Aarhus, Denmark; Department of Surgery, Aarhus County Hospital, Aarhus, Denmark.Institute of Human Genetics University of Aarhus DK-8000 Aarhus C, DenmarkSearch for more papers by this authorJørgen Glenn Lauritsen, Jørgen Glenn Lauritsen Department of Clinical Genetics, Karolinska Hospital, Stockholm, Sweden; Institute of Human Genetics, University of Aarhus, Aarhus, Denmark; Department of Surgery, Aarhus County Hospital, Aarhus, Denmark.Search for more papers by this authorJan Lindsten, Jan Lindsten Department of Clinical Genetics, Karolinska Hospital, Stockholm, Sweden; Institute of Human Genetics, University of Aarhus, Aarhus, Denmark; Department of Surgery, Aarhus County Hospital, Aarhus, Denmark.Search for more papers by this author First published: June 1972 https://doi.org/10.1111/j.1601-5223.1972.tb01018.xCitations: 9AboutPDF ToolsExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume71, Issue1June 1972Pages 168-171 ReferencesRelatedInformation

Mechanisms giving rise to triploid zygotes during assisted reproduction

To review information on the origin of triploid zygotes as gathered from assisted reproduction techniques. Identification of relevant literature by a MEDLINE search and own experience on the basis of cytogenetic studies of abnormally fertilized oocytes. None. None. None. None. Penetration of two haploid spermatozoa or of a single diploid spermatozoon into the oocyte causes diandric triploidy. The first case can be discerned by formation of a total of three pronuclei, whereas the second process will remain undetected, because it involves a female and a single but diploid male pronucleus. Digynic triploidy after intracytoplasmic sperm injection is characterized by nonextrusion of the second polar body and formation of three pronuclei. Digyny can also result from the fertilization of diploid giant oocytes. Depending on how maturation of these gametes proceeds, three or only two pronuclei will be observed. Thus, the size of the pronuclear stage must be considered for a successful identification of the abnormality. Endoreduplication within the female pronucleus is not detectable and may represent another, albeit rare, origin of digynic triploidy. Routine inspection of the number of pronuclei is not an absolutely reliable tool for excluding the development of triploid embryos. Observations during assisted reproduction may yield valuable information on the origin of triploidy.

Diploid sperm and the origin of triploidy.

Trisomy 16, the 45,X monosomy and triploidy are the more frequent chromosome anomalies in spontaneous abortions. Earlier estimations, based on frequencies of diandric triploidy at conception, resulted in a good correlation with the frequencies of diploid sperm in infertile males (up to 1.9%). Recent data have shown that most diandric triploids originate by dispermy, although 8.3% of them are produced by diploid sperm resulting from meiotic errors. Using these data, the estimated frequency of diploid sperm is still in good correlation with the percentage above. Furthermore, analysis of male pronuclei (PN) in 3PN zygotes produced by ICSI with sperm from oligo-, crypto- and azoospermic males revealed that 33.3% of them were diploid, while none of the PN produced by normozoospermic males by IVF was. The estimated frequency of diploid sperm in these infertile males is also in good correlation with the previous figures. The data suggest that most diandric triploids are produced by normozoospermic males by dispermy, while most diandric triploids produced by oligozoospermic males would result from fertilization by unreduced, diploid sperm.

Frequency and origin of triploidy in the fire ant Solenopsis invicta

A large microsatellite survey of fire ants of both social forms (monogyne and polygyne) from both the native and introduced ranges (Argentina and the U.S.A.) revealed surprisingly high levels of triploidy (12%) in non-reproductive females from an introduced polygyne population in Georgia, U.S.A. Triploid females were not detected among reproductive (egg-laying) queens from this population, among females from monogyne populations in the introduced range or among females of either social form from the native range. The results of complementary analyses with allozyme markers were highly concordant with the individual microsatellite ploidy designations and confirmed the general patterns in the distribution of triploidy observed with microsatellites. Triploidy in the Georgia polygyne population is hypothesized to be linked to the high frequency of diploid males in this population; although most such males are sterile, 2.4% were found to possess functional reproductive tracts and presumably produce diploid sperm. Mating of such males with polygyne queens is expected to give rise to triploid females at levels close to those observed. Diploid males are absent in monogyne populations and uncommon in the introduced range, thus explaining the lack of triploid females in samples from these sources. The absence of triploid reproductive queens in the Georgia polygyne population may result from subviability of triploid queens or execution of such queens by workers. Our results suggest that triploid females of social Hymenoptera may be more common than appreciated and are most likely to be found in populations with substantial numbers of fertile diploid males.

Polyploidies in abortion material decrease with maternal age.

Among 639 spontaneous abortions between the 8th and 14th week of gestation 342 (53.5%) revealed an abnormal karyotype. While the rate of trisomies distinctly increased with advancing maternal age, a decrease in the rate of 45,X conceptuses and polyploidies was observed among abortions from older women. The overall relation of XXXX:XXYY among the tetraploidies was 14:11 and that of XXX:XXY:XYY among the triploidies was 26:36:1. However, when the latter was related to maternal age, a reversal of the XXX:XXY ratio of 1:2 in the younger to 2:1 in the older age groups became evident. Furthermore a decrease in the rate of "paternally" derived partial hydatidiform moles was found among the triploid abortion specimens from older women. From these observations we conclude that digyny plays a major role in the origin of triploidy in the increased maternal age groups, while diandry related to immaturity of oocytes and impairment of oocyte cortical function is more frequent in triploid abortions from younger women.

Triploidy in Paragonimus westermani

The finding of triploid and diploid forms of Paragonimus westermani in Japan has caused tremendous controversy over the identity and speciation of this parasite. Should these two genetically different forms be given different specific names? Hirohiso Hirai and Takeshi Agatsuma have studied the lung flukes by using cytogenetic techniques and zymodeme analysis. In this article, they briefly compare triploid P. westermani with the diploid form and develop a hypothesis for the mechanism and origin of triploidy.

Karyotype and Meiotic Behaviour of the TriploidCrocus SativusL.

SUMMARYThe karyotype and microsporogenesis of triploid Crocus sativus were studied. The high percentage of trivalents observed at metaphase I (on average, 7.3 trivalents per cell) together with the karyotype configuration confirm autotriploidy. Some considerations about the presence of one unique chromosome in the karyotype and about the origin of triploidy are presented.

Origin of triploidy in spontaneous abortuses.

Fourteen triploid spontaneous abortuses were studied cytogenetically by sequential Q and C banding and the marker chromosomes were compared with those of the parents. The abortuses comprised all triploid cases in a series of 288 consecutive abortuses of the first 16 weeks of pregnancy occurring in one hospital. In 12 of the triploids the origin of the extra haploid set was conclusively determined, revealing six cases of dispermy, five failures in the first maternal and one failure in the first paternal meiotic division. The results were combined with those of five other studies comprising a total of 48 informative cases. Non-reduction in the second meiotic division seems to be of little or no significance in the origin of human triploidy. Dispermy is the predominant source, accounting for 40--50% of the triploid spontaneous abortuses. Non-reduction in the first meiotic division of the father seems to be the second-most frequent source although in the present material the corresponding maternal non-reduction is much more common.

Origin of triploidy and tetraploidy in man: 11 cases with chromosomes markers.

Sixteen triploid and one tetraploid human abortuses were studied for the origin of polyploidy using a sequential Q- and R-banding technique. Ten triploid abortuses provided informative data: one originated in the maternal first meiotic division; five apparently resulted from dispermy; two derived from an error during either the paternal second meiotic division or the first mitotic division; and the last two were of paternal origin. The results indicate that paternal factors, especially dispermy, are the predominant sources of triploidy in man. The tetraploid abortus showed duplication of both the maternal and paternal haploid sets, suggesting normal division of chromosomes and suppression of cytoplasmic cleavage at the first mitotic division. No correlation was found between the origin of polyploidy and the phenotype of the triploid abortuses, nor between the origin of polyploidy and the maternal use of oral contraceptives.

Oogenesis and chromosomal heterozygosity in the thelytokous midge, Lundstroemia parthenogenetica (Diptera, Chironomidae).

The thelytokous triploid midge Lundstroemia parthenogenetica (Diptera: Chironomidae:Chironominae), 3n = 9, is always found to be heterozygous for two inversions and a deletion. Parthenogenesis is maintained by an apomiotic restitutional oogenesis as found in the subfamily Orthocladiinae. This mechanism is compared with other groups exhibiting a restitutional or disordered first division. Possible modes of evolution of the apomictic restitutional system, origin of triploidy in apomictic forms, and chromosomal polymorphisms are discussed.

ISO-chromosomes and the origin of triploidy in hybrids between old and new world species ofPhiladelphus

1. AllPhiladelphus species in nature are diploids 2n=26. 2. The chromosome complement of species examined was found to be fairly uniform in morphology and could be represented by the haploid formulae. $$1 L_m + 8 M_{st} + 2 S_{st} + 2 S_{sm} .$$ 3. The L chromosome inPhiladelphus was found to be an iso-chromosome with a weak centromere. 4. While geographical isolation inPhiladelphus has not appreciably affected pairing between the 12 pairs of chromosomes in hybrids, it has a distinct effect on the pairing of iso-chromosomes. 5. Pollen fertility of species and hybrids is related to the behaviour of iso-chromosome. 6. Triploidy in interspecific hybrids is due to the formation of unreduced gametes by non-separation of iso-chromosomes at meiosis.

Note on the origin of triploidy in maize

Triploid individuals in maize occur through the fertilization of diploid or unreduced eggs by haploid sperm. The diploid eggs have arisen by complete non-disjunction of the entire chromosome set during meiosis or through non-disjunction during one of the three mitotic divisions of the female gametophyte. In either of these eventualities, however, the female gamete carried the diploid number of chromosomes.