CAMK2A and obesity due to melanocortin 4 receptor deficiency: Compared to AAV-CaMKIIα-EGFP-injected male mice (hereafter, CTL group), AAV-CaMKIIα-Cre-EGFP-injected male mice (hereafter, CKO group) exhibited progressive obesity, with a ~ 2-fold increase in body weight gain observed two months after AAV injection (Fig. 1D, E).