Adaptation in these genes may not be exclusive to these populations, but soils across Central-South Asian have particularly high levels of magnesium131,132 and both genes have been linked to hypomagnesemia (HOMG2 [MIM:154020]), either directly (FXYD2132) or indirectly (MECOM, associated with osteoporotic fractures that can be caused by hypomagnesemia133,134). Here, FXYD2 is linked to familial primary hypomagnesemia.