Replication stress causes delayed mitotic entry and chromosome 12 fragility at the ANKS1B large neuronal gene in human induced pluripotent stem cells.

Substantial background level of replication stress is a feature of embryonic and induced pluripotent stem cells (iPSCs), which can predispose to numerical and structural chromosomal instability, including recurrent aberrations of chromosome 12. In differentiated cells, replication stress-sensitive genomic regions, including common fragile sites, are widely mapped through mitotic chromosome break induction by mild aphidicolin treatment, an inhibitor of replicative polymerases. IPSCs exhibit lower apoptotic threshold and higher repair capacity hindering fragile site mapping.

Generation of induced pluripotent stem cell line (RCMGi008-A) from human skin fibroblasts of a cystic fibrosis patient with compound heterozygous F508del/CFTRdele2.3 mutations in CFTR gene.

Skin fibroblasts obtained from a 20-year-old woman with clinically manifested and genetically proven (F508del/CFTRdele2.3) cystic fibrosis were successfully transformed into induced pluripotent stem cells (iPSCs) by using Sendai virus-based reprogramming vectors including the four Yamanaka factors, OCT3/4, SOX2, KLF4, and c-MYC. The iPSCs showed a normal karyotype, expressed pluripotency markers and exhibited the potential to differentiate into three germ layers in spontaneous differentiation assay.

Pattern of chromosomal aberrations persisting over 30 years in a Chernobyl Nuclear Power Plant accident survivor: study using mFISH.

The long-term in vivo cytogenetic effects of high-dose radiation exposure can be traced in accidentally irradiated persons, and particularly useful for developing strategies of monitoring and therapy of such patients, as well as for elucidating the fundamental aspects of hematopoiesis and radiobiology. Using 24-color fluorescent in situ hybridization (mFISH), we analysed the frequency and the spectrum of chromosomal aberrations (CA) in peripheral blood lymphocytes of the Chernobyl Nuclear Power Plant (NPP) accident victim 30, 31, 32 and 33 years after acute accidental exposure to high-dose gamma radiation of the whole body. Totally, 993 metaphase cells were analyzed (or 219, 272, 258, 244 cells each year), of which 297 were aberrant.

The FRA14B common fragile site maps to a region prone to somatic and germline rearrangements within the large GPHN gene.

Common fragile sites (cFSs) represent parts of the normal chromosome structure susceptible to breakage under replication stress. Although only a small number of cFSs have been molecularly characterized, genomic damage of cFS genes appears to be critical for the development of various human diseases. In this study, we fine mapped the location of FRA14B and showed that the fragile region spans 765 kb at 14q23.

Toxic and DNA damaging effects of a functionalized fullerene in human embryonic lung fibroblasts.

Water-soluble fullerenes have been studied as potential nanovectors and therapeutic agents, but their possible toxicity is of concern. We have studied the effects of F-828, a soluble fullerene [C60] derivative, on diploid human embryonic lung fibroblasts (HELFs) in vitro. F-828 causes complex time-dependent changes in ROS levels.