The development of the Down syndrome phenotype

This month’s practitioners meeting involved an interesting and fruitful discussion of a new paper published in Infants and Children. The author, Deborah Fidler, of Colorado State University has been working in the field of genetic syndromes associated with intellectual disabilities, including Down syndrome since 1997. This paper clearly and concisely reviews the growing body of research into the already well-established concept of the behavioural phenotype associated with Down syndrome.[1,2] However, the major focus of the paper is to examine the profile from a developmental perspective, i.e. whether the so-called ‘typical’ (and some might say ‘inevitable’) profile presented by the majority of individuals in childhood and adolescence is already present and/or becoming established in infancy. She frames this question within the context of early intervention, highlighting the necessity of creating a curriculum and style of delivery, which is grounded in scientific research evidence regarding children with the specific diagnosis of Down syndrome and not a programme that simply fits a wider target audience of children with developmental delay. This review does not aim to describe the typical profile as Sue Buckley reviewed this very clearly in her article ‘Specificity in Down syndrome’ in the last issue.[4] Instead, the aim is to draw out the conclusions of Deborah’s paper with regard to the development across time of the phenotype and some of the implications of this for early intervention and school support.