BACKGROUND AND AIMS The obstetric care of a pregnancy, as it is practiced today, includes non-invasive screening approaches as well as invasive procedures for the definitive prenatal diagnosis of fetal disorders correlations between indications for prenatal cytogenetic diagnosis and results of the chromosomal analysis made upon fetal cells. The aim of our study was to evaluate the correlations ...

Amplification of MYCN is the signature genetic aberration of 20-25% of neuroblastoma and a stratifying marker associated with aggressive tumor behavior. The detection of heterogeneous MYCN amplification (hetMNA) poses a diagnostic dilemma due to the uncertainty of its relevance to tumor behavior. Here, we aimed to shed light on the genomic background which permits hetMNA in neuroblastoma and ti...

Currently, approximately 3000 species of stick insects are known; however, chromosome numbers, which range between 21 and 88, are known for only a few of these insects. Also, centromere banding staining (C-banding) patterns were described for fewer than 10 species, and fluorescence in situ hybridization (FISH) was applied exclusively in two Leptynia species. Interestingly, 10-25% of stick insec...

Cell suspension cultures derived from 8 sugarcane (ISaccharvm species hybrid) varieties were studied. Chromosome numbers (2n) varied from 92 to 191, with a mean at 111, in cells of a colchicine-free suspension culture of F 164 of which the donor's number was 108. The numbers rose to as many as 309 when the cells were treated with 100 ppm colchicine. Similar results were observed for other varie...

Few reports have been published on cytogenetics in crickets of the subfamily Nemobiinae. Within the Neotropical region the karyotypes of only two species are known, both of them belonging to the genus Phoremia. In the present paper, chromosomes of a third Neotropical species, Zucchiella atlantica Mello 1990 (Orthoptera: Trigonidiidae), have been studied and a cytological review of other species...

Background & Aims: Chromosome abnormalities are a major cause of miscarriage and neonatal mortality. The present study aimed to determine the association of fetal and parents chromosomal abnormalities with congenital anomalies. Methods: A cross-sectional study was performed in a tertiary referral center (Afzalipour Hospital) over 16 months period (2011-2012). The study groups consisted of 77 fe...

Ninety individuals of the characid fish Astyanax fasciatus (Cuvier, 1819) were collected at Água da Madalena stream (Botucatu, São Paulo, Brazil) and analyzed for diploid chromosome number 2n and karyotype composition as well as for the chromosomal location of the 5S and 18S ribosomal DNA (rDNA). Whereas no chromosome differences were associated with sex, three different karyomorphs with diploi...

Nearly 260 taxa and chromosomal races of subfamily Chrysomelinae have been chromosomally analyzed showing a wide range of diploid numbers from 2n = 12 to 2n = 50, and four types of male sex-chromosome systems. with the parachute-like ones Xy(p) and XY(p) clearly prevailing (79.0%), but with the XO well represented too (19.75%). The modal haploid number for chrysomelines is n = 12 (34.2%) althou...

LIMITED understanding of leukemogenesis and the A neoplastic phenotype of transformed lymphoid progenitors has been a major obstacle to the development of safe, uniformly effective therapy for children with acute lymphoblastic leukemia (ALL). Studies of isoenzymes, immunologic markers, and other expressions of cell phenotype provide valuable clues to ALL etiology, but ultimately they fail to di...

T decades ago, Todd (1) postulated that wholesale fission of all ‘‘mediocentric’’ (metacentric, submetacentric, and subtelocentric) chromosomes in a complement plays a major role in chromosome evolution. According to Todd, karyotypic fission produces, as a consequence of a single mutational ‘‘event,’’ dramatic differences in the diploid numbers of closely related species (2, 3). A diversity of ...