Hypogonadotropic hypogonadism was also induced in pigs by Sonstegard et al. (2016), Sonstegard et al. (2017), who developed the first large animal model of impaired kisspeptin system when they knocked out KISS1R in pigs using TALENs (Tan et al., 2013), demonstrating that kisspeptin signaling is vital for sexual maturation of boars. This evidence concerns the gene KISS1 and hypogonadotropic hypogonadism.