PABPN1 and oculopharyngeal muscular dystrophy: The N-terminal part of this protein contains a short polyalanine tract (Met-(Ala)10x-Gly-(Ala)2x ... ), and in OPMD a small GCG expansion adding 1 to 8 alanine, or a missense mutation of the +12 glycine into an alanine resulting in a contiguous stretch of 13 alanine, leads to a modified PABP2 protein that interfere with the cellular traffic of polyadenylated RNA (Brais et al., 1998; Robinson et al., 2006).