The same twins taking part in the mole study return at age 16 to take part in MAPS, the Mental Abilities and Performance Study. Twins are tested for complex reaction time, inspection time, working memory and evoked potentials are recorded. The aim is to estimate the extent to which these measurements are genetically influenced, and, eventually, to use linkage analysis to locate the major genes. So far over 400 pairs and a substantial number of siblings have been tested. The role of triplet repeat expansions of normal cognitive functioning is being investigated.
(N.G. Martin, M. Wright, A. Eldridge, M. Grace, N. Hansel, M. Luciano, in collaboration with Profs. G & L Geffen and Dr. G. Smith, The University of Queensland)