Here are some known facts:
1. MECP2 Duplication Syndrome results in deficient interferon gamma that produces poor resistance to certain kinds of infection.
2. Individuals with MECP2 Duplication Syndrome often develop osteoporosis.
3. Individuals with MECP2 Duplication Syndrome are at risk for bone fractures.
4. Interferon Gamma plays a significant role in the formation and maintenance of bones.
SO, it seems likely that the low levels of interferon gamma might be responsible for low bone density and frequent fractures in individuals with MECP2 Duplication Syndrome.
Of course, it is not that simple. There may be a lot of other factors that contribute to low bone density in these individuals. Until someone does the research, we don’t really know why these fractures occur or what (if anything) we can do about it.
Duque G, Huang DC, Dion N, Macoritto M, Rivas D, Li W, Yang XF, Li J, Lian J, Marino FT, Barralet J, Lascau V, Deschênes C, Ste-Marie LG, Kremer R. Interferon-γ plays a role in bone formation in vivo and rescues osteoporosis in ovariectomized mice. Journal of Bone Mineral Research. 2011 Jul;26(7):1472-83. doi: 10.1002/jbmr.350.
Yang T, Ramocki MB, Neul JL, Lu W, Roberts L, Knight J, Ward CS, Zoghbi HY, Kheradmand F, Corry DB.Overexpression of methyl-CpG binding protein 2 impairs T(H)1 responses.Science Translational Medicine. 2012 Dec 5;4(163):163ra158. doi: 10.1126/scitranslmed.3004430.