FISH and Chimps: Insights into Frequency and Distribution of Sperm Aneuploidy in Chimpanzees (Pan troglodytes)

Abstract

Numerical chromosomal aberrations in sperm are considered to be a major factor in infertility, early pregnancy loss and syndromes with developmental and cognitive disabilities in mammals, including primates. Despite numerous studies in human and farm animals, the incidence and importance of sperm aneuploidies in non-human primate remains mostly undetermined. Here we investigated the incidence and distribution of sperm aneuploidy in chimpanzees (Pan troglodytes), the species closest to human. We identify evolutionary conserved DNA sequences in human and chimpanzee and selected homologous sub-telomeric regions for all chromosomes to build custom probes and perform sperm-FISH analysis on more than 10,000 sperm nuclei per chromosome. Chimpanzee mean autosomal disomy rate was 0.057 ± 0.02%, gonosomes disomy rate was 0.198% and the total disomy rate was 1.497%. The proportion of X or Y gametes was respectively 49.94% and 50.06% for a ratio of 1.002 and diploidy rate was 0.053%. Our data provide for the first time an overview of aneuploidy in non-human primate sperm and shed new insights into the issues of aneuploidy origins and mechanisms.

Cytochalasin D restores nuclear size acting on F-actin and IZUMO1 localization in low-quality spermatozoa

“…For chromosome territory size and position analysis, samples were hybridized with MetaSystems whole-chromosome painting probes XCP 9 (D-0309), XCP 11 (D-0311), XCP 17 (D-0317), XCP 21 (D-0321), XCP 22 (D-0322), XCP X (D-0323). For intertelomeric analysis, samples were hybridized with homemade probes built as described previously 32 with 9p probe consisting of 5 bacterial artificial chromosome clones (RP11-996P21, RP11-675G5, RP11-696A8, RP11-960F12 and CTD-2537D15) covering a 1 Mb distance, and a 9q probe consisting of 8 bacterial artificial chromosome clones (RP11-937L7, RP11-417A4, RP11-48C7, CTD-2377P2, RP11-350O14, RP11-673E5, RP11-769N4 and CTD-2551F21) covering a 1.2 Mb distance. For chromocenter analysis, samples were hybridized with Pan-centromeric probe (1695-F-01 from Cambio, Cambridge, England).…”