High-throughputSNPgenotypingplatformsuseautomatedgenotypecallingalgo-rithmstoassigngenotypes.Whilethesealgorithmsworkefficientlyforinpidualplatforms,theyarenotcompatiblewithotherplatforms,andhaveinpidualbiasesthatresultinmissedgenotypecalls.HerewepresentdataontheuseofasecondcomplementarySNPgenotypeclusteringalgorithm.ThealgorithmwasoriginallydesignedforinpidualfluorescentSNPgenotypingassays,andhasbeenopti-mizedtopermittheclusteringoflargedatasetsgeneratedfromcustom-designedAffymetrixSNPpanels.Inananalysisofdatafroma3Karraygenotypedon1,560samples,theadditionalanalysisincreasedtheoverallnumberofgenotypesbyover45,000,significantlyimprovingthecompletenessoftheexperimentaldata.Thisanalysissuggeststhattheuseofmultiplegenotypecallingalgorithmsmaybead-visableinhigh-throughputSNPgenotypingexperiments.ThesoftwareiswritteninPerlandisavailablefromthecorrespondingauthor.