BCHE and obesity due to melanocortin 4 receptor deficiency: Besides mean BChE activity tending to be higher in obese than in unobese individuals (Chautard-Freire-Maia et al., 1991; Alcântara et al., 2003; Furtado-Alle et al., 2008), BChE itself is also related to ghrelin (Kojima et al., 2001), a peptide associated with obesity (Tschöp et al., 2001), through its hydrolyzing and inactivating the latter (De Vriese et al., 2004).