In writing this chapter, we set out to illustrate some of the problems that have beset the study of obesity genetics, to evaluate some of the techniques currently available and to provide some examples of the progress made to date and future prospects for this rapidly moving field. In the past few years alone, fascinating and specific new lines of investigation have been suggested by unravelling the genetic and molecular basis of elements of the leptin pathway and of syndromic forms of obesity such as the BBS.

In the future, continuing refinements to genetic tools for the identification of new candidate genes as well as functional analysis and exploration of gene–gene and gene–environment interactions offer the potential for insights into complex polygenic inheritance scarcely thinkable only a few years ago. The tempo of significant discovery will doubtless increase following publication of the human and mouse genomic DNA sequences together with increasingly precise functional annotation of these sequences. 

Improvements in the characterization and promulgation of common SNPs throughout the genome are likely to facilitate the study of genetic association and it may now only be a matter of time before the possibility of conducting studies of LD throughout large areas of the human genome becomes realized.

Combined with routine access to huge, almost ‘real-time’ on-line data repositories, better computational tools and the increasing ease of collaborative study, we are now able to look forward with much greater hope than has hitherto been possible to the achievement of fundamental insight into the genetic biology of obesity in coming years.

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