Mutations in the SRY gene prevent the differentiation of the fetal gonads to testes and cause developing female phenotype, and as a result sex reversal and pure gonadal dysgenesis (Swyer syndrome) can be developed. Different types of mutations identified in the SRY gene are responsible for 15% of the gonadal dysgenesis. In this study, we report a new mutation (R132P) in the High Mobility Group (HMG) region of SRY gene was detected in a patient with primary amenorrhea who has 46,XY karyotype. This mutation leads to replacement of the polar and basic arginine with a nonpolar hydrophobic proline residue at aminoacid 132 in the nuclear localization signal region of the protein. With this case report we want to emphasize the genetic approach to the patients with gonadal dysgenesis. If Y chromosome is detected during cytogenetic analysis, revealing the presence of the SRY gene and identification of mutations in this gene by sequencing analysis is become important in.
Keywords: Amenorrhea, Gonadal dysgenesis, HMG box, SRY gene, Swyer syndrome