a recent study has clearly shown that obesity is more prominent in PHP-Ia patients than PPHP patients [144]. Thus, it appears that Gsα may be imprinted in more tissues than currently recognized, such as in parts of the brain that controls satiety and body weight. It is also possible that disruption of other imprinted GNAS gene products contribute to the pathogenesis of AHO. Supporting this hypothesis, chondrocytes with paternal Gnas exon 2 disruption exhibit a slightly, but significantly, higher degree of Gsα haploinsufficiency than chondrocytes with maternal Gnas exon 2 disruption [143]. More detailed characterization of the different AHO features between patients with paternally and maternally inherited Gsα mutations are likely to provide further insights into the understanding of the mechanisms underlying AHO.
