- X linked myotubular myopathy (MTM1) maps between DXS304 and DXS305, closely linked to the DXS455 VNTR and a new, highly informative microsatellite marker (DXS1684). Dahl, N., Samson, F., Thomas, N.S., Hu, L.J., Gong, W., Herman, G., Laporte, J., Kioschis, P., Poustka, A., Mandel, J.L. J. Med. Genet. (1994)