Transgenic mice expressing a chimeric LH beta (LHβ) subunit that includes the C‐terminal portion of the beta subunit of chorionic gonadotropin, exhibit high levels of LH, reflecting a condition of infertility and miscarriages.[54] Compared to control mice, these mice also show increased levels of testosterone and estradiol, infrequent ovulation, a prolonged luteal phase, ovarian cyst formation, and granulosa cell tumors.[58, 59] Additionally, these mice routinely display metabolic disorders, including obesity and elevated insulin levels.[60]. The gene discussed is PLOD1; the disease is obesity due to melanocortin 4 receptor deficiency.