New versions of annotation packages for chips are available for downloading in the metaData section of Bioconductor. NULL values in the GO environment are replaced by NA to make the multiget function happy. The XXXCHRLOC packages (e. g. humanCHRLOC) has a new environment called XXXCHRLOCCYTOLOC that contains the physical location of cytobands on each chromosome. Examples of usage of this environment are shown below: > library(mouseCHRLOC) > ls(mouseCHRLOCCYTOLOC) [1] "1" "10" "11" "12" "13" "14" "15" "16" "17" "18" "19" "2" "3" "4" "5" [16] "6" "7" "8" "9" "X" "Y" > bandsOn1 <- get("1", mouseCHRLOCCYTOLOC) > names(bandsOn1) [1] "qA1" "p" "qA2" "qA3" "qA4" "qA5" "qB" "qC1.1" "qC1.2" [10] "qC1.3" "qC2" "qC3" "qC4" "qC5" "qD" "qE1.1" "qE1.2" "qE2.1" [19] "qE2.2" "qE2.3" "qE3" "qE4" "qF" "qG1" "qG2" "qG3" "qH1" [28] "qH2.1" "qH2.2" "qH2.3" "qH2.3" "qH3" "qH4" "qH5" "qH6" > bandsOn1[["qA1"]] Start End 0 1476405 > bandsOn1[["qE4"]] Start End 128939338 139766306 For R 1.9.0 > mouseCHRLOCCYTOLOC[["1"]][["qA1"]] Start End 0 1476405 > mouseCHRLOCCYTOLOC[["1"]][["qE4"]] Start End 128939338 139766306 Please let me know if you have any concerns. Thanks. Jianhua