Some studies reported that a particular semaphorin, semaphorin 3A, encoded by human SEMA3A, on chromosome 7p12.1, if mutated both in humans and mice, could lead to abnormal migration of GnRH neurons to the hypothalamus, leading to hypogonadism and infertility [94–96] (Figure 1). This evidence concerns the gene GNRH1 and hypogonadism.