Generation of Rhesus Macaque Embryos with Expanded CAG Trinucleotide Repeats in the Gene.

Huntington's disease (HD) arises from expanded CAG repeats in exon 1 of the () gene. The resultant misfolded HTT protein accumulates within neuronal cells, negatively impacting their function and survival. Ultimately, HTT accumulation results in cell death, causing the development of HD.

CRISPR/Cas9 editing of the MYO7A gene in rhesus macaque embryos to generate a primate model of Usher syndrome type 1B.

Mutations in the MYO7A gene lead to Usher syndrome type 1B (USH1B), a disease characterized by congenital deafness, vision loss, and balance impairment. To create a nonhuman primate (NHP) USH1B model, CRISPR/Cas9 was used to disrupt MYO7A in rhesus macaque zygotes. The targeting efficiency of Cas9 mRNA and hybridized crRNA-tracrRNA (hyb-gRNA) was compared to Cas9 nuclease (Nuc) protein and synthetic single guide (sg)RNAs.

Blastocyst development after fertilization with in vitro spermatids derived from nonhuman primate embryonic stem cells.

Objective: To demonstrate that functional spermatids can be derived in vitro from nonhuman primate pluripotent stem cells.

Design: Green fluorescent protein-labeled, rhesus macaque nonhuman primate embryonic stem cells (nhpESCs) were differentiated into advanced male germ cell lineages using a modified serum-free spermatogonial stem cell culture medium. In vitro-derived round spermatid-like cells (rSLCs) from differentiated nhpESCs were assessed for their ability to fertilize rhesus oocytes by intracytoplasmic sperm(atid) injection.