- Chromosome 1p21.3 microdeletions comprising DPYD and MIR137 are associated with intellectual disability. Willemsen, M.H., Vallès, A., Kirkels, L.A., Mastebroek, M., Olde Loohuis, N., Kos, A., Wissink-Lindhout, W.M., de Brouwer, A.P., Nillesen, W.M., Pfundt, R., Holder-Espinasse, M., Vallée, L., Andrieux, J., Coppens-Hofman, M.C., Rensen, H., Hamel, B.C., van Bokhoven, H., Aschrafi, A., Kleefstra, T. J. Med. Genet. (2011)