Testicular regression syndrome UMLS:C0266427 Vanishing testes syndrome UMLS:C1261504 Vanishing testis syndrome MESH:C537770 UMLS:C0405582 ETRS MedDRA:10002641 TRS Embryonic testicular regression syndrome Testicular regression syndrome (TRS) is a developmental anomaly characterized by the absence of one or both testicles with partial or complete absence of testicular tissue. TRS may vary from normal male with unilateral no-palpable testis through phenotypic male with micropenis, to phenotypic female. The phenotype depends on the extent and timing of the intrauterine accident in relation to sexual development. ICD10:Q55.0 OMIM:273250 orphanet Male infertility due to gonadal dysgenesis