Improved evidence for linkage on 6p and 5p with retrospective pooling of data from three asthma genome screens

To improve our ability to identify genes for complex diseases, evaluation o f new methods that retrospectively pool genotype and phenotype data collect ed by multiple centers is important. Availability of three whole-genome scr eens enabled us to compare two methods, pooling raw data and meta-analysis. Multipoint linkage analyses were performed on two outcomes, total serum Ig E levels and asthma affection status, using an improved Haseman-Elston algo rithm. Two regions showed stronger evidence for linkage using covariate-adj usted pooled data, compared with any individual sample. Both methods for po oling data identified strong linkage to Z-transformed log(e)IgE levels at a location between D6S1019 and D6S426, and to the asthma trait at D5S268. In conclusion, retrospective analysis of pooled genome scan data is a potenti ally powerful and useful method to examine both positive and negative evide nce for linkage of quantitative and categorical phenotypes across populatio ns. (C) 2001 Wiley-Liss, Inc.