Mayer–Rokitansky–Küster–Hauser (MRKH) syndrome type 2 is characterized by congenital uterovaginal agenesis associated with a variable spectrum of extragenital anomalies. Affected individuals typically have a normal female
karyotype (46,XX), preserved ovarian function, and normal development of secondary sexual characteristics. The gynecological presentation most commonly includes primary
amenorrhea due to absence of the uterus and the upper two-thirds of the vagina, often identified during adolescence or early adulthood. Extravaginal manifestations distinguish type 2 (atypical) MRKH and may involve multiple organ systems. Renal anomalies are among the most frequent findings and include pelvic kidneys, horseshoe kidney, or renal agenesis. Skeletal abnormalities are also common and may present as vertebral fusion, scoliosis, butterfly vertebrae, or cervical ribs, reflecting disruptions in axial skeletal development. Additional reported anomalies include gastrointestinal malformations such as annular pancreas and rare hepatic variants, such as castor tail-like liver. Cardiovascular involvement, although less frequent, can be clinically significant. Congenital heart defects such as atrial septal defects may remain undiagnosed until adulthood and can manifest with progressive dyspnea, palpitations, peripheral cyanosis, pulmonary hypertension, or cerebrovascular events secondary to paradoxical embolism. Symptoms may be insidious and attributed to other conditions, contributing to delayed diagnosis. The clinical presentation of MRKH type 2 is therefore heterogeneous and depends on the number and severity of associated malformations. This variability underscores the importance of systematic multisystem evaluation in individuals diagnosed with MRKH to allow early detection and management of potentially serious associated anomalies. ==Genetics==