Report of an XX male with hypospadias and pubertal gynecomastia, SRY gene negative in blood leukocytes but SRY gene positive in testicular cells.

Most XX male subjects present an anomalous translocation of the sex-determining region of the chromosome Y (SRY) gene from chromosome Y to chromosome X. Several explanations have been proposed for the differentiation of testicular tissue in the absence of SRY gene. A patient is presented in whom the SRY gene was absent in peripheral leukocytes but present in testicular tissue. This possibility should always be ruled out before diagnosing Y-negative XX maleness.