A deletion at the polled P_C locus alone is not sufficient to cause a polled phenotype in cattle.

ABSTRACT: Dehorning is a common practice in the dairy industry, but raises animal welfare concerns. A naturally occurring genetic mutation (P_C allele) comprised of a 212 bp duplicated DNA sequence replacing a 10-bp sequence at the polled locus is associated with the hornless phenotype (polled) in cattle. To test the hypothesis that the 10 bp deletion alone is sufficient to result in polled, a CRISPR-Cas9 dual guide RNA approach was optimized to delete a 133 bp region including the 10 bp sequence. Timing of ribonucleoprotein complex injections at various hours post insemination (hpi) (6, 8, and 18 hpi) as well as in vitro transcribed (IVT) vs synthetic gRNAs were compared. Embryos injected 6 hpi had a significantly higher deletion rate (53%) compared to those injected 8 (12%) and 18 hpi (7

SUBMITTER: Hennig SL 

PROVIDER: S-EPMC8825853 | biostudies-literature | 2022 Feb

REPOSITORIES: biostudies-literature