23andMe is currently carrying out SNP genotyping of the ALSPAC cohort across approximately 580,000 common SNPs with genome-wide coverage. We are using a custom version of the Illumina HumanHap 550+ platform with additional content selected by 23andMe. The additional content includes coverage of known common and rare SNP associations; better coverage of drug metabolizing genes; and dense coverage of the Y chromosome, mitochondrial DNA, and the MHC region. The 23andMe customer cohort and the ALSPAC cohort have substantial differences in demographics, and phenotypes have been assessed very differently. Essentially all 23andMe customer phenotype data is self reported through web based surveys, and unlike ALSPAC, the 23andMe cohort is far from being a cross section of an identifiable population. As a result, we think it is most appropriate to model SNP associations separately in the two cohorts and then combine association test results in a meta-analysis. For this initial data access proposal, we have enumerated a subset of the ALSPAC phenotypes we are interested in. We would use this data for exploratory purposes, for selection of appropriate models to be used later for genome-wide SNP association testing. We would also use the data to familiarize ourselves with the ALSPAC resource. The association analysis will be conducted later in collaboration with Drs. David Evans and Nic Timpson. In cases where an association has reached genome wide significance in the 23andMe cohort alone, the ALSPAC data can be used as an independent replication. We also expect that additional loci will be revealed with genome-wide significance in the combined meta-analysis. In some cases, we plan to develop new surveys for the 23andMe cohort around research questions that have been examined in ALSPAC, and will perform meta-analyses for those phenotypes later after new survey data is collected. We think the area of host genetic susceptibility to common infectious disease is particularly interesting and not well studied, despite substantial public health impacts. This includes categorical phenotypes for one-time infections such as measles or mumps, as well as quantitative phenotypes such as frequency of upper respiratory infection and ear ache. We have already identified several associations with infectious disease in the 23andMe customer cohort, and will attempt to replicate these in the ALSPAC cohort. We do not have the resources or domain knowledge to focus a substantial effort on the analysis of any one phenotype. As a result, our plan is to focus on phenotypes that can be assessed from at most a few survey or clinical exam responses, or where summary derived variables are already available. In the phenotype areas for which we have requested data, we have existing survey data and GWAS results in the 23andMe cohort for laterality, bitter taste perception, myopia, some infections, and dental health. We are planning to deploy surveys for post-partum depression, and have requested related ALSPAC data. We have also requested data for coordination and non-verbal perception tests, where we are considering new surveys. Several existing 23andMe surveys measure components of personality, however the metrics we are using are somewhat different from the ones used in ALSPAC. We plan additional work to identify where there is overlap and where we may want to deploy additional surveys in the 23andMe cohort.