Abstract: The present invention relates generally to a method for detecting abnormalities or a propensity for an abnormality to occur in an animal such as a human. The abnormality of the present invention relates generally to conditions arising from interruption in signalling associated with receptor-type tyrosine kinase-like molecules and in particular RYK (related to tyrosine kinase) receptors. Such abnormalities include aberrations in the normal morphogenesis of craniofacial structures including secondary palate as well as a range of aberrations resulting in neural conditions affecting angiogenesis and conditions affecting muscle development or maintenance. The present invention permits the early diagnosis of such defects and conditions such as in utero and provides a means for genetic or other therapeutic intervention.