WWOX and neoplasm: Parkin is located in the third most common fragile site, FRA6E, proposed to be involved in several types of cancer, acting as a tumor suppressor gene together with other common fragile site genes such as FHIT (FRA3B ; 3p14.2) and WWOX (FRA16D ;16q23) that are also associated with exon deletions [43,51].