BRD2 and cartilage-hair hypoplasia: Unfortunately, classic spermatogenic treatment–human chorionic gonadotrophin (hCG) monotherapy or combined gonadotropin treatment (hCG+FSH)–is much less successful in men with severe CHH (testes <4 mL), particularly those with history of bilateral cryptorchidism, than in men with HH of postpubertal-onset, e.g., due to acquired pituitary disease (42).