Genetic and Epigenetic Factors Affecting Blastomere Fragmentation in Two-Cell Stage Mouse Embryos

• Published in: Biology of reproduction Vol. 65; no. 4; pp. 1050 - 1056
• Main Authors: Hawes, S M, Gie Chung, Y, Latham, K E
• Format: Journal Article
• Language: English
• Published: Madison, WI Society for the Study of Reproduction 01-10-2001
• Subjects: Amanitins - pharmacology; Animals; Biological and medical sciences; Blastomeres - physiology; Blastomeres - ultrastructure; Early stages. Segmentation. Gastrulation. Neurulation; Embryology: invertebrates and vertebrates. Teratology; Enzyme Inhibitors - pharmacology; Female; Fetal Death - genetics; Fundamental and applied biological sciences. Psychology; Genotype; In Situ Nick-End Labeling; Male; Mice; Mice, Inbred AKR; Mice, Inbred C3H; Mice, Inbred C57BL; Mice, Inbred DBA; RNA Polymerase II - antagonists & inhibitors; Superovulation; Transcription, Genetic; Zygote - physiology; Zygote - ultrastructure; Vertebrata; Embryo; Mammalia; Mouse; Rodentia; Genetics; Early stage; Blastomere; Apoptosis; Fragmentation
• ISSN: 0006-3363; 1529-7268
• DOI: 10.1095/biolreprod65.4.1050

We report here that mouse embryos can exhibit a significant incidence of blastomere fragmentation at the two-cell stage. The
incidence of this is influenced by both the maternal and paternal genotype. Embryos from C57BL/6 mothers exhibit a very low
incidence of fragmentation at the two-cell stage in crosses involving males of C57BL/6, DBA/2, AKR/J, or SJL strains but exhibit
a significantly increased incidence of fragmentation in crosses involving C3H/HeJ males. Increased fragmentation is seen in
embryos from C3H/HeJ females crossed with C57BL/6 males but not with C3H/HeJ males. Embryos obtained from reciprocal (C57BL/6
× C3H/HeJ) F 1 hybrid females also exhibit an increased incidence of fragmentation at the two-cell stage when the hybrid females are mated
to either C57BL/6 or C3H/HeJ males. Interestingly, the results differ significantly between reciprocal F 1 hybrid females, indicating a parental origin effect, possibly a result of either genomic imprinting or differences in mitochondrial
origin. We conclude that the incidence of blastomere fragmentation at the two-cell stage in the mouse is under the control
of more than one genetic locus. We also conclude that blastomere fragmentation is affected by both parental genotypes. These
results are relevant to understanding the genetic control blastomere fragmentation, which may contribute to evolutionary processes,
affect the success of procedures such as cloning, and affect the outcome of assisted reproduction techniques.