BACKGROUND Over the past 2 years, noninvasive prenatal testing (NIPT), which uses massively parallel sequencing to align and count DNA fragments floating in the plasma of pregnant women, has become integrated into prenatal care. Professional societies currently recommend offering NIPT as an advanced screen to pregnant women at high risk for fetal aneuploidy, reserving invasive diagnostic proced...

Meiotic synapsis and recombination between homologs permits the formation of cross-overs that are essential for generating chromosomally balanced sperm and eggs. In mammals, surveillance mechanisms eliminate meiotic cells with defective synapsis, thereby minimizing transmission of aneuploidy. One such surveillance mechanism is meiotic silencing, the inactivation of genes located on asynapsed ch...

Abstract Background Fetal growth restriction (FGR) is associated with increased risks for complications before, during, and after birth, in addition to risk of disease through adulthood. Although placental insufficiency, failure supply the fetus adequate nutrients, underlies most cases FGR, its causes are diverse not fully understood. One few diagnosable insufficiency ongoing pregnancies presen...

Aneuploidy in human eggs is the leading cause of pregnancy loss and several genetic disorders such as Down syndrome. Most aneuploidy results from chromosome segregation errors during the meiotic divisions of an oocyte, the egg's progenitor cell. The basis for particularly error-prone chromosome segregation in human oocytes is not known. We analyzed meiosis in more than 100 live human oocytes an...

The XYY anomaly has been recognized since 1961 (Dunn et al, 1961; Sandberg et al, 1961), but in contrast to other sex chromosome aneuploidies, no consistent clinical syndrome associated with it has emerged. The phenotypes are wide ranging, but generally are tall normal males. Most interest in the syndrome has centred on the possibility that abnormal behaviour may be an associated feature. The f...

infertility affects approximately 15% of couples worldwide. within 50% of cases, man provides reproductive function disorders (1). the cause of infertility in men with oligospermia and azoospermia seems to be due to underlying genetic abnormalities (2). chromosomal abnormalities are one of the causes of human infertility as they interfere with spermatogenesis. the frequency of chromosomal aberr...

Background: The present study offers our contribution on the topic by a retrospective analysis of the prevalence of chromosomal abnormalities in a population of Iranian infertile men attending assisted reproduction programs. Materials and Methods: Cytogenetic analysis was performed according to standard methods on cultured cells obtained from the patient peripheral blood. In all, 874 files belo...

A reciprocal translocation between the short arm of chromosome 1 and the long arm of chromosome 3 was observed in a pedigree of three carriers (proband, and his brother and mother). In this study, the three carriers had different clinical manifestations: the proband with infertility, his brother with spousal miscarriages, and his mother with no adverse reproductive history. Cytogenetic analysis...

OBJECTIVE To examine the performance of chromosome-selective sequencing of cell-free (cf) DNA in maternal blood for assessment of fetal sex chromosome aneuploidies. METHODS This was a case-control study of 177 stored maternal plasma samples, obtained before fetal karyotyping at 11-13 weeks of gestation, from 59 singleton pregnancies with fetal sex chromosome aneuploidies (45,X, n = 49; 47,XXX...

We conducted a cytogenetic study on 865 individuals with idiopathic mental retardation (MR) who were admitted to the Cytogenetics Department of the Iran Blood Transfusion Organisation (IBTO) Research Centre, Tehran, Iran; these were performed on blood samples using conventional staining methods. Chromosome anomalies were identified in 205 of the patients (23.6%). The majority were Down's syndro...