The Y-chromosome carries definitive determinants of male sexuality, its coexistence with female phenotypic features must result from failure at some level of the normal developmental sequence (Wolman et al. 1985). The determination of phenotypic sex occurs at various levels and is ultimately the result of the interactions among them. To examine the influences of the Y-chromosome on sexual phenotype, these three levels-chromosomal, gonadal and the somatic constituents of internal and external genitalia-must be considered (Jacobs and Ross 1966; Muller 1985; Pembrey and Roberts 1985; Rusell 1985). The present paper reports clinical and chromosomal studies done on seven patients. All are phenotypically females but with 46, XY chromosome constitution. Of the seven cases presented, three are siblings and exhibit very similar clinical features. Interestingly, five of these patients have been diagnosed with malignant gonads. These cases pose some questions on the definite role, function or control of the Y-chromosome (and the genes on the chromosome) on sex determination, etiology of the ovarian organogenesis, and the high tumor risk in these individuals.