ACTRT2 and obesity due to melanocortin 4 receptor deficiency: Meanwhile, evidence from a large cohort study with 10,665 patients consulting for a semen analysis demonstrated that increased BMI had an adverse effect on semen quality (44), and the result of a label-free quantitative LC-MS/MS proteomic analysis indicated that declines in endoplasmic reticulum protein 57 (ERp57) and actin-binding-related protein T2 (ACTRT2) expression may play critical roles in reducing sperm motility, thereby contributing to obesity-induced asthenozoospermia (45).