KL and disorder of glycogen metabolism: For a long time, lymphatic vessels were thought to be absent from the bone, but in recent studies, they have been confirmed,14 and during the development of GSD, GLA, and KLA, the normal bone of the patients is resorbed by the invading lymphatic vessels.129–133 The proliferation of lymphatic vessels in GSD and KLA is associated with hyperactivation of Rat sarcomavirus and Mitogen-activated kinase (RASMEK) pathway in VEGF-C/VEGFR3 signaling induced by somatic mutations.