Abstract: Compositions and methods for fetal or in utero delivery of active agents are provided. The compositions are most typically administered intravenously via the vitelline vein, umbilical vein, or directly into the amniotic cavity of a pregnant mother. Fibroblast growth factor is to correct structural defects of neural tissue.

Abstract: Methods for gene editing of embryos in vitro are provided. The methods typically include contacting an embryo in vitro with an effective amount of non-enzymatic (e.g., non-nuclease) gene editing active agent(s) optionally encapsulated, entrapped, complexed to or dispersed in polymeric particles to induce at least one alteration in the genome of the embryo. The embryo can be a single cell zygote, however, treatment of male and female gametes prior to fertilization, and embryos having 2, 4, 8, or 16 cells, and including not only zygotes, but also morulas and blastocysts are also provided. Typically, the embryo is contacted with the particles on culture days 0-6 during or following in vitro fertilization.

Abstract: Compositions and methods for fetal or in utero delivery of active agents are provided. The compositions are most typically administered intravenously via the vitelline vein, umbilical vein, or directly into the amniotic cavity of a pregnant mother. Growth factors can be delivered to correct structural defects. Gene editing can be carried out utilizing a gene editing composition such as triplex-forming molecules, CRISPR, zinc finger nucleases, TALENS, or others. The methods can include administration of a gene modification potentiating agent such as stem cell factor (SCF), a CHK1 or ATR inhibitor, or a combination thereof. A particularly preferred gene editing composition is triplex-forming peptide nucleic acids (PNAs) substituted at the ? position for increased DNA binding affinity. Polymeric particle compositions for extracellular and intracellular delivery of the active agents are also provided.