Abstract

Huntington's disease (HD) is an inherited neurodegenerative disorder, characterised by psychiatric changes, cognitive disonance and motoric dysfunctions. The mutation responsible for this fatal disease is an abnormally expanded polyQ repeat within the gene encoding the huntingtin (htt) protein. Unfortunately, there is no specific cure available to stop disease progression. Numerous drugs have been developed to produce benefits in this disease, however, preclinical tests are required for confirmation of their effectiveness in treating HD. There are different animal models, each model with its own advantages and limitations, but there is still a huge demand for large animal models for testing the possibilities of HD therapies. As the extensive neuroanatomical and physiological studies indicate, a close similarity of the miniature pig brain to the human brain exists in term of neurochemical and neurotransmitter repertoire. Hence we chose this model for the generation of a transgenic model of HD. Lentiviral constructs encoding N terminal truncated (548aa) htt with 145 polyQ repeats under the control of human HD promoter were microinjected into the one cell stage embryos. The offspring born after embryo transfer were genotyped and one female piglet was transgenic. Both mutant htt incorporation into genome and its mRNA expression were proved using PCR. Western blot analysis confirmed the presence of the mutant htt protein. The transgenic gilt was mated with its brother to produce F1 generation. Three of eight newborn piglets are transgenic. The suitable and publicly acceptable large animal model of HD that can serve to validate the efficacy of treatment approaches targeted to modulate HD was generated. Mutant htt gene incorporated into porcine genome is not only transcribed into mRNA but is also expressed at the protein level. HD transgenic miniature gilt successfully conceived and delivered eight healthy offsprings. Three male piglets are transgenic in the litter.