Chromosome segregation and interchromosomal effect were studied in spermatozoa from a carrier of a pericentric chromosome 17 inversion, 46,XY,inv(17)(p13.1q25.3). Sperm chromosome segregation, lymphocytes of the inversion carrier, and cells from his offspring were analysed by multicolour fluorescence in situ hybridization. The frequency of balanced sperm was 73%. An unusual segregation of recombinants was observed, viz. deletion of the p arm (14.6%) or duplication of the p arm with the presence of one q arm (8.4%), instead of the expected recombinants, viz. duplication of one arm with deletion of the other and vice versa. These unusual recombinants were explained by the position of the 17q breakpoint, which was between the q arm telomere-associated repeats and the unique q subtelomere region. The offspring of the donor were found to have a 17p deletion including the Miller-Dieker critical region, similar to the most frequent recombinant sperm class. The disomy frequency was significantly increased for chromosome 17 compared with other autosomes, suggesting that pairing and recombination of the inversion may predispose to non-disjunction. There was no significant difference between the frequencies of aneuploidy for chromosomes 13, 21, X and Y in the chromosome inversion heterozygote compared with controls. Thus, this unique pericentric inversion of chromosome 17 produces unusual recombinant products; no evidence was apparent of an interchromosomal effect in any of the tested chromosomes.
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J Neurol
January 2025
Centre de Génétique Humaine, Centre Hospitalier Universitaire de Besançon, Besançon, France.
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View Article and Find Full Text PDFPLoS Genet
January 2025
Department of Zoology, University of British Columbia, Vancouver, British Columbia, Canada.
The synaptonemal complex (SC) is a protein-rich structure essential for meiotic recombination and faithful chromosome segregation. Acting like a zipper to paired homologous chromosomes during early prophase I, the complex is a symmetrical structure where central elements are connected on two sides by the transverse filaments to the chromatin-anchoring lateral elements. Despite being found in most major eukaryotic taxa implying a deeply conserved evolutionary origin, several components of the complex exhibit unusually high rates of sequence turnover.
View Article and Find Full Text PDFSci Adv
January 2025
Department of Materials Science and Engineering, Shenzhen Key Laboratory of Full Spectral Solar Electricity Generation (FSSEG), Southern University of Science and Technology, No. 1088, Xueyuan Rd., Shenzhen 518055, Guangdong, China.
Owing to the predominant merit of tunable bandgaps, tin-lead mixed perovskites have shown great potentials in realizing near-infrared optoelectronics and are receiving increasing attention. However, despite the merit, there is still a lack of fundamental understanding of the bandgap variation as a function of Sn/Pb ratio, mainly because the films are easy to segregate in terms of both composition and phase. Here, we report a fully stoichiometric synthesis of monocrystalline FAPbSnI nanocrystals as well as their atomic-scale imaging.
View Article and Find Full Text PDFCytoskeleton (Hoboken)
January 2025
Department of Life Sciences, University of Siena, Siena, Italy.
We analysed here the dynamic of the kinesin-like Pavarotti (Pav) during male gametogenesis of wild-type and Sas4 mutant flies. Pav localizes to the equatorial region and the inner central spindle of late anaphase wild-type spermatogonia and displays a strong concentration at the midbody during late telophase. At metaphase of the first meiotic division, Pav shows widespread localization on the equatorial region of the spermatocytes.
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