CPT1B and obesity due to melanocortin 4 receptor deficiency: For instance, Calabuig-Navarro et al. found that obesity increased placental CPT2 mRNA expression, but decreased that of CPT1B and acylcarnitine content (Calabuig-Navarro et al., 2017), while Bucher et al. showed that CPT1A and CPT2 protein expression and acylcarnitines (16:0, 18:2, and 20:4) were reduced only in the placentas of female offspring (female placenta) among women with obesity (Bucher et al., 2021).