Further investigation offers the chance to understand the role of this allele in diabetes and growth. All the Decode findings reported were in adults. We now wish to use ALSPAC to investigate the following hypotheses:

1. the minor allele increases birthweight, BMI, weight and height in children, from birth throughout growth and maturity. We propose to examine all cross sectional time points , from birth to teenage years (the latest measurements), and if the data look positive, growth trajectories.

2. the association with BMI is driven by adiposity. We propose to examine DEXA derived measures of fat mass and lean mass at age 9 (as we did with FTO, ref Science 2007) and any other available ages

3. the minor allele when present in the mother increases growth in children (BMI, weight and height) . We propose to test the maternal allele's effect on offspring measures , correcting and stratifying by offspring genotype.

4. Exploratory analysis of glycaemic and adipokine measures - fasting glucose, and insulin, adiponectin, leptin and FFAs.