title: The Majority of Resorptions in Old Mice Are Euploid.
abstract: Chromosomal abnormality is a leading cause of aging-related infertility, spontaneous abortion and congenital birth defects in humans. Karyotype analyses of spontaneously aborted human fetuses reveal high proportions (~50%) being chromosomal abnormal with the majority being trisomies of various chromosomes. As a model organism, mice are widely used for studies of reproduction and reproductive aging. Like older women, older mice exhibit high incidences of early embryo death. However, it is not known if aneuploidy is prevalent amongst resorptions in older mice. We have karyotyped 65 retarded/resorbed fetuses in 10-month-old C57BL/6 mice, and found that 55 (84.6%±8.8%, with 95% confidence) were euploid. Similarly, of 40 such fetuses from 17 month-old C57BL/6 mice, we found 38 (95±7%, with 95% confidence 95%) being euploid. Therefore, aneuploidy is not a leading cause of embryo death in older mice.
authors.affiliation: Ottawa Hospital Research Institute, The Ottawa Hospital-General Campus, 501 Smyth Road, Box 511, Ottawa, Ontario, K1H 8L6, Canada.
authors.forename: Yong
authors.initials: Y
authors.lastname: Tao
authors.affiliation: Ottawa Hospital Research Institute, The Ottawa Hospital-General Campus, 501 Smyth Road, Box 511, Ottawa, Ontario, K1H 8L6, Canada.|Department of Obstetrics and Gynaecology, and Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada.
authors.forename: X Johné
authors.initials: XJ
authors.lastname: Liu
mesh_terms: D000375:Aging / Q000502:physiology; D000782:Aneuploidy; D000818:Animals; D020964:Embryo Loss / Q000453:epidemiology / Q000235:genetics*; D005260:Female; D007621:Karyotyping / Q000379:methods; D008297:Male; D051379:Mice; D011247:Pregnancy