Subjects with 46,XY gonadal dysgenesis (Swyer syndrome) have a distinctive phenotype. They are normal or tall in stature, lack somatic anomalies, and possess bilateral rudimentary gonads. Critical Yp deletions have been described in some cases, but in the majority no defects at the molecular level have been reported. To verify the presence or absence of SRY, the putative testicular-determining factor gene, specific primers were designed to amplify the conserved region of the SRY gene. Deoxyribonucleic acid from control males (n = 10) and sex-reversed females with the Swyer syndrome phenotype (n = 5) generated the anticipated 310 bp band. This Y-specific band was absent in the deoxyribonucleic acid from control females (n = 9). To search for possible point mutations, the amplified products of all study subjects and one control male were sequenced in both orientations. The base pair sequences were all identical and similar to the previously published report.