Degree Type


Date of Award


Degree Name

Doctor of Philosophy


Biochemistry, Biophysics and Molecular Biology

First Advisor

Carol M. Warner


The rate of cleavage divisions of preimplantation mouse embryos has been shown to be influenced by the Ped gene, a gene linked to the mouse major histocompatibility complex, the H-2 complex. Studies were undertaken to investigate Ped gene expression independent of the uterine environment and to show formal linkage of the Ped gene to the Qa region of the H-2 complex. Development of embryos from inbred and congenic mouse strains in vitro, in chemically defined medium, revealed that differences in the rate of cleavage division between slow developing strains (Ped slow) and fast developing strains (Ped fast) are maintained in vitro. The Ped phenotype of developing embryos is an intrinsic property of the embryos themselves. Through formal genetic linkage studies, co-segregation of Ped gene phenotype and expression of Qa-2 antigen were found in backcross embryos. These data show that the Ped gene is linked to the Qa region;Preliminary studies were undertaken to examine the role of the Ped gene in embryo survival. The Ped gene, by influencing the rate of preimplantation embryo development, does not appear to be a factor in determining embryo survival in the backcrosses studied;The role of the Qa-2 antigen, a Qa region protein, in reproduction was studied. Qa-2 and maternal effects on birth weights and litter size were found in B6.K1, B6.K2, and F[subscript]1 crosses;Finally, the hypothesis that the Qa-2 antigen is the Ped gene protein product is presented and discussed.



Digital Repository @ Iowa State University,

Copyright Owner

Melody Sue Bartel Brownell



Proquest ID


File Format


File Size

301 pages

Included in

Biochemistry Commons