Much of the Y chromosome consists of large palindromic arrays harboring genes that are critical for spermatogenesis. In this issue, Lange et al. (2009) show that although gene conversion within these arrays maintains their integrity, it also permits rare unequal sister chromatid-exchange events within palindromes that create unstable dicentric chromosomes, resulting in infertility, sex reversal...

Dose-rate effects on chromosome aberrations in the low-dose-rate range have not been evaluated previously. The incidences of chromosome aberrations were analysed in splenic lymphocytes from female specific pathogen-free (SPF) C3H mice that were continuously irradiated with low- or medium-dose-rate (LDR, MDR) (137)Cs γ rays from 56 days of age to evaluate the dose-rate effects. The dose-response...

Abstract Chromosome fusions threaten genome integrity and promote cancer by engaging catastrophic mutational processes, namely chromosome breakage–fusion–bridge cycles chromothripsis. are frequent in cells incurring telomere dysfunctions or those exposed to DNA breakage. Their occurrence therefore their contribution instability unchallenged is unknown. To address this issue, we constructed a ge...

In a young male with Fanconi's anaemia, 10% of cells in a direct bone marrow preparation had chromosome abnormalities. Breaks involving primarily groups B and C members constituted the most frequent changes encountered, while 2 cells had either a dicentric or a ring chromosome. Smears from the same aspirate showed anaphase bridges in 3oo of mitoses. It is suggested that in this disease chromoso...

A case of maternal uniparental disomy of chromosome 13 is described. The subject is a phenotypically normal male who inherited a t(13;13)(p11.2;p11.2) from his mother who is a carrier of this translocation. The mother was ascertained through a history of recurrent abortion and is phenotypically normal. The translocation in both subjects was studied by cytogenetic and DNA analysis and appears to...

Background: Lymphocyte-dicentric assay is the most generally accepted method for biological dosimetry of overexposed individuals. In this study, the frequency of unstable chromosome aberration in blood lymphocytes was used to estimate radiation dose received by individuals. Evaluation of dose using a calibration curve produced elsewhere may have a significant uncertainty therefore, experiments ...

We report on a newborn white male infant with marked dysmorphic features and various congenital malformations. The initial clinical evaluation showed Crouzon-like features as well as some features of trisomy 18 syndrome and trisomy 13 syndrome. The results from conventional cytogenetic analysis showed a structurally abnormal chromosome replacing one normal chromosome 18, but only by applying mo...