*** Overview *** The VCF files contain small indel calls for the CEU and YRI trios. The calls were made from MAQ-aligned Broad-recalibrated Illumina BAM files, using the indel caller Dindel (Albers et al). 454 and SOLID data were not considered in the analysis, not for the actual calling and also not for the detection of candidate indels. *** Procedure *** The calls were made as follows: 1. Extract all indels in MAQ alignments from the BAM file. These are the candidate indels. 2. Generate genotype likelihoods using Dindel for every candidate indel 3. Assuming Mendelian inheritance, calculate the posterior probability for each indel genotype in all three trio members jointly. Thus, the VCF files only contain indels that are consistent with Mendelian inheritance. Independent analysis of the trio members indicated that there is signficant number of cases where the trio-child shows evidence for an indel, but none of the parents does; these cases are not included in the VCF file. Such cases are likely explained by reduced sensitivity for detecting indels as compared to SNPs, mapping errors, and some may be a result of de novo mutations. We hope to address these issues in future releases by using more sensitive mapping and indel calling algorithms. NOTE As described above, all reported calls are consistent with Mendelian inheritance by construction. These VCFs are therefore not useful for mutation analysis. NOTE The second sample in the genotype file is that father, the third is sample is the mother. If you have any questions, please contact me (Kees) at caa (at) sanger.ac.uk Kees Albers Gerton Lunter Richard Durbin