genetics nonhuman Article 208 controlled study 150 human 147 Humans 135 Animals 123 animal 123 metabolism 117 animal experiment 79 male 68 mouse 67 female 59 unclassified drug 59 animal model 55 gene expression 54 animal tissue 50 article 47 procedures 44 animal cell 42 Male 41 Mice 40 adult 40 chemistry 40 gene expression regulation 39 pathology 38 protein expression 37 Female 35 in vitro study 33 physiology 32