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Author ORCID Identifier


Campus-Only Access for Five (5) Years

Document Type


Degree Name

Doctor of Philosophy (PhD)

Degree Program

Animal Biotechnology & Biomedical Sciences

Year Degree Awarded


Month Degree Awarded


First Advisor

Jesse Mager

Subject Categories

Developmental Biology


Mammalian embryogenesis is a dynamic process involving rapid cell proliferation and multiple cellular differentiation events. The early stage of development consists of many milestones that the embryo must achieve prior to progressing through gestation. These critical developmental benchmarks are governed by multiple genes including those for survival. The International Mouse Phenotyping Consortium (IMPC) has generated over 6,000 gene knockout mouse lines to date and 24% of the mouse strains are identified as embryonic lethal. Our goal is to characterize homozygous knockout mouse embryos that lack both alleles of these lethal genes, identify the stage of lethality, and investigate their role in early embryonic development. Our lab has characterized over 100 embryonic lethal strains and performed detailed analysis on 10 different knockout mouse lines. Presented here are 6 knockout mouse lines – Dynein Axonemal Assembly Factor 2 (Dnaaf2) and 5 members of the Mitochondrial Ribosomal Protein (Mrp) genes in which morphology of the homozygous knockout mouse embryos and their littermates are drastically different. More importantly, none of these embryos are viable beyond embryonic day (E) 9.5 signifying the importance of these genes during early developmental stages. The largescale analysis of over 100 of the homozygous knockout mouse lines reveals developmental bottlenecks that are present in early embryogenesis. Our analysis provides insight into the function of these essential genes during early embryogenesis as well as the process of development as a whole.


Creative Commons License

Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.