Multifactor　dimensionality　reduction　(MDR)　is　originally　proposed　to　identify　gene-gene　and　gene-environment　interactions　associated　with　binary　traits.　Some　efforts　have　been　made　to　extend　it　to　quantitative　traits　(QTs)　and　ordinal　traits.　However　these　methods　are　still　not　computationally　efficient　or　effective.　In　this　paper,　we　propose　Fuzzy　Quantitative　trait　based　Ordinal　MDR　(QOMDR)　to　strengthen　identification　of　gene-gene　interactions　associated　with　a　quantitative　trait　by　first　transforming　it　to　an　ordinal　trait　and　then　using　a　fuzzy　balance　accuracy　measure　based　on　generalized　member　function　of　fuzzy　sets　to　select　best　sets　of　SNPs　as　having　strong　association　with　the　trait.　Experimental　results　on　two　real　datasets　show　that　our　algorithm　has　better　consistency　and　classification　accuracy　in　identifying　gene-gene　interactions　associated　with　QTs.　©　2016　IEEE.