Triploidy Research Articles

Application of quantitative fluorescence PCR for the prenatal diagnosis of common fetal chromosomal aneuploidies

OBJECTIVE To assess the value of quantitative fluorescence PCR (QF-PCR) for the prenatal diagnosis of common fetal chromosomal aneuploidies. METHODS A total of 2436 amniotic fluid samples were collected at 18 to 22 gestational weeks. Multiplex QF-PCR was performed with fluorescence-labeled primers specific for 32 polymorphic short tandem repeat (STR) sites on chromosomes 21, 18, 13, X and Y. The PCR products were assayed by capillary electrophoresis. All samples were also assayed by karyotyping. RESULTS Seventy-six (3.12%) samples were diagnosed as chromosomal aneuploidies by QF-PCR, among which 51 were trisomy 21, 12 were trisomy 18, 2 were trisomy 13, and 1 was triploidy. The results were all consistent with those of karyotyping. Ten samples were suspected as sex chromosomal aneuploidies, among which 9 were confirmed, except for 1 case with X structural abnormality. In addition, karyotyping has diagnosed 24 (0.99%) cases of structural abnormalities, only one of which was suspected by QF-PCR with partial abnormal STR results. Two (0.08%) samples were found to be mosaic by karyotyping, one of which was suggested by QF-PCR with cut-off ratios of STR markers. CONCLUSION QF-PCR is reliable for the diagnosis of numerical abnormalities of chromosomes 21, 18, 13, X and Y. The method can serve as an effective technique for rapid prenatal screening of common chromosome aneuploidies in fetus.

Potential Application of Triploidy Induction in Important Aquatic Species in South East Asia

Triploidy, a stage of having 3 sets of chromosomes, occurs naturally in fish. Induction of triploidy is possible by subjecting newly fertilized eggs to sub-lethal conditions prior to the extrusion of polar bodies. The purposes of the induction include improving growth and/or obtaining sterile animals for various purposes. This article gives a brief background of triploid induction in aquatic animals, performances of triploid and collective information on triploidy induction in aquatic species native to South East Asia, and future direction.

Clinicopathologic features and prognostic factors of malignant phyllodes tumors

To study the clinicopathologic features of malignant phyllodes tumors (PT) by histopathologic analyses, immunohistochemical profiling and DNA content assay, and evaluation of the clinical outcome. Ten patients with malignant PT from 1999 to 2013 who were treated by surgery were enrolled in this study. The morphologic characteristics were studied under light microscope, standard two-step EnVision method of immunohistochemical staining was used to assess the expression of CK5/6, CKpan, 34β E12, desmin, p63, ER-α, PR, Ki-67, CD34, SMA, p53, p16, bcl-2 and CD117 in the tumors. The corresponding paraffin blocks were also used for flow cytometric DNA content assay. These data were correlated with the follow-up results. The median age of onset was 46.5 years old. The mean tumor size was 7.4 cm (2.0-25.0 cm). At the end of the follow-up period (22 to 125 months), there were tumor recurrences in 3/8 patients and the median time of recurrence was 24 months. Metastasis occurred in 3/8 patients who all died of the tumors. PT had heterogeneous histology, with stromal overgrowth with leaf-like projections, periductal stromal overgrowth, and most commonly, diffuse stromal overgrowth with sarcomatous differentiation. The mean positive index of Ki-67 was 11.4%. The stromal tumor cells were positive for CD34, SMA, p53, p16, and bcl-2 in 3/10, 9/10, 6/10, 8/10, and 4/10 cases, respectively. CD117,ER-α and PR were negative. Interpretable DNA histograms were obtained in nine cases with triploidy in two cases. The diagnosis of malignant PT should be considered based on the diversity of growth patterns and heterogeneous histology.Ki-67 and CD34 are valuable diagnostic and prognostic factors in patients with malignant PT. Tumors with diffuse stromal overgrowth, heterologous elements, Ki-67 ≥ 20% or aneuploidy are more likely to metastasize.

ELECTROPHORETIC STUDIES OF HYBRIDS OF WATER FROGS (RANA EPEIROTICA, R. BALCANICA) IN THE IONIAN ZONE OF GREECE

ABSTRACT Natural hybrids of Rana epeirotica and Rana balcanica were studied by means of vertical acrylamide electrophoresis to confirm the various types of hybrids distinguished by the bioacoustic method. On the basis of four diagnostic loci (Ldh-1, Mdh-1, a muscle protein, and plasma albumin) at least three types of hybrids are distinguished. The most common type is the typical intermediate hybrid, which at all four loci displayed the two alleles of the parent species in the form of typical heterozygosity. Other types of hybrids give evidence of triploidy with either two genomes of R. balcanica and one of R. epeirotica, or one genome of R. balcanica and two of R. epeirotica. The possible role of the hybrid types is discussed.

Roles of p57KIP2 immunohistochemistry and flow cytometry in diagnosis of molar pregnancy

To study the value of combined use of paternally imprinted gene product p57(KIP2) immunohistochemistry and flow cytometry in the differential diagnosis of placental hydropic diseases. A total of 32 cases of hydropic placenta with DNA polymorphism information were collected, and the genetic results were used as basis for the diagnosis of complete hydatidiform moles (CHM), partial hydatidiform moles (PHM) or hydropic abortions. All cases were examined by histology, p57(KIP2) immunohistochemical staining (EnVision method) and flow cytometry DNA ploidy analysis. The p57(KIP2) immunohistochemical staining and DNA ploidy results were compared with the genetic results. In CHM, p57(KIP2) negative rates were 95.2% (20/21), whereas all the 11 cases of non-CHM (7 cases PHM and 4 cases hydropic abortions) were positive (11/11). In 11 p57(KIP2) -positive cases, 7 cases with triploidy and 4 cases with diploidy by flow cytometry were proven to be PHM and hydropic abortions by genetic analysis, respectively. Overall, 96.9% (31/32) cases of hydropic placentas were correctly diagnosed by combined use of p57(KIP2) immunohistochemistry and flow cytometry. p57(KIP2) immunohistochemical negativity is a reliable index for the diagnosis of CHM. Combined flow cytometry DNA ploidy and p57(KIP2) immunohistochemistry are useful in the pathological differentiation of CHM, PHM and hydropic abortions.

Induction of Triploidy in Clarias Gariepinus by Heat Shock of Fertilized Eggs

Eggs and milt were collected from female and male Clarias gariepinus respectively. Fertilized eggs were given heat-shock at 40 and 41 o C for 4.5 minutes duration. The eggs were shocked at different post fertilization periods viz: immediately after fertilization, 2, 3, 4, 5 and 6 mins after fertilization. Percentage hatchability for 40 o C heat shock treatment gave 10, 14, 38, 42 and 68.7% for 2, 3, 4, 5 and 6 mins post fertilization periods respectively. While in 41 o C heat-shock treatment 14, 28 36, 52 and 41% were recorded for the 36%, 52 and 41% were recorded for the same post fertilization period. All eggs shocked immediately after fertilization at both 40 and 41 o C died. At 40 o C heat shock treatment, chromosome examination using 48 h old embryo gave 100, 80, 20 and 0% triploidy for 3, 4, 5 and 6 minutes post fertilization periods respectively. heat-shock treatment at 41 o C recorded 75, 100, 100 and 80% triploidy at 3, 4, 5 and 6 minutes post fertilization periods respectively. The fry of eggs shocked at 2 mins after fertilization died within 12 hours. Thus, chromosome examination was not carried out. The results of this work thus revealed that 100% triploidy could be successfully induced in C. gariepinus by heat-shock at 40 o C,sStarting 3 minutes after fertilization for 4.5 minutes.

A. Note on Triploidy of the Funa

A. Note on Triploidy of the Funa

TRIPLOIDY (AND HAPLOIDY) IN THE NEWT, TRITURUS VIRIDESCENS, INDUCED BY REFRIGERATION OF FERTILIZED EGGS

TRIPLOIDY (AND HAPLOIDY) IN THE NEWT, TRITURUS VIRIDESCENS, INDUCED BY REFRIGERATION OF FERTILIZED EGGS