06-P005 Rab23 regulates cell migration independent of hedgehog signalling in zebrafish: new insight into the Carpenter syndrome phenotype

ing the duplication generates increased levels of EFNB1 transcript, compared to the normal chromosome. We also show that imbalance of ephrin-B1 between X chromosomes in a mouse model containing a hypomorphic Efnb1 conditional allele results in aberrant cell mixing of the cranial primordia during development and hypertelorism. Taken together these data suggest that cellular mosaicism for different levels of ephrin-B1 (as well as simple presence/absence) is an important contributor to craniofacial abnormalities in humans and mice.