Biological Asymmetry and Handedness[editors, Gregory R. Bock and Joan Marsh] - Novartis Foundation Symposia

Biological Asymmetry and Handedness Chairman: L. Wolpert 1991 Morphological asymmetry occurs in most types of living organisms, often with a systematic bias towards either right-handed or left-handed forms. The predominance of L-amino acids can be explained thermodynamically; their characteristics determine secondary structure in proteins but the information is lost at the next stage of protein assembly. Left-right asymmetry in animals arises early in embryogenesis: the mechanism is unknown but examples from a range of organisms - including ciliates, molluscs, Caenorhabditis, Xenopus and mammals - provide several clues. Evidence from fossils suggests that primitive animals were asymmetrical; bilateral symmetry then evolved, followed by the laterality seen in modern chordates - for example, the displacement of the mammalian heart to the left. So far, only one gene involved in the inheritance of laterality, the mouse iv gene, has been identified. Cerebral lateralization is observed anatomically; the relationship of this to human handedness' is not clear.;Similarly, whether models for the inheritance of handedness share any features with those for the inheritance of anatomical asymmetries is an open question. Was there an ancestral left-right gene that gave rise to a family of homologues which specify morphological and functional handedness? This multidisciplinary book, the first on this topic for twenty years, discusses models for the inheritance of anatomical asymmetry and for the inheritance of human handedness. Other recent Ciba Foundation Symposia: No. 144 Cellular basis of morphogenesis Chairman: L. Wolpert 1989 ISBN 0 471 92306 0 No. 155 Myopia and the control of eye growth Chairman: J. Wallman 1990 ISBN 0 471 92692 2 No. 160 Regeneration of vertebrate sensory receptor cells Chairman: E.W. Rubel 1991 ISBN 0 471 92960 3