Phenotipic Variability of Diphalia. Three cases report from the Hospital para el Niño Poblano. México. L. Cuellar1, J. Aparicio2,6, P.M. Barrientos3, H.M.L Hurtado4, G.R. Vargas5 1) Urology and Pediatric Surgery; 2) Genetics; 3) Endocrinology; 4) Cytogenetics; 5) Pathology, Hospital Para El Nino Poblano; 6) Estomatology, Benemérita Universidad Autónoma de Puebla, México.

   Code Words: Diphallia, hipospadias, homebox genes. INTRODUCTION. Diphallia, or penile duplication (PD), is a medical condition in which a male infant is born with two penises. It has been estimated that one out of 5 million live births in the United States results in a diphallic birth defect. When diphallia is present, a different kind of other congenital anomalies such as renal, vertebral and anorectal duplication are observed. There is also a higher risk of spina bifida. Infants born with PD and its related conditions have a higher death rate from various infections associated with their more complex renal or colorectal systems. CLINICAL CASES. A study was performed in three male patients 2 months, 4 and 16 years respectivelly. All patients were diagnosed with real diphallia, well developed with urinarious meatus, and both testicles, one of the case a vessel duplication was observed, all of the patients has a normal cariotype, 46XY. Pathology studies were performed to the surgered penises. CONCLUSION. It is thought diphallia occurs in the fetus between the 23rd and 25th days of gestation when an injury, chemical stress, or malfunctioning homeobox genes hamper proper function of the caudal cell mass of the fetal mesoderm as the urogenital sinus separates from the genital tubercle and rectum to form the penis. This rare condition has been documented in pigs and other mammals. It is commonly mistaken that all sharks have this condition, but in reality they have a pair of "claspers" which serve a reproductive function. REFERENCES. 1. Sergio F. Camacho-Gutierez y cols. Genitourinary reconstruction in a case of penis duplication associated to bladder duplication, perineal hypospadias and bowel sequestration. Rev Mexicana de Urologia.2004:64:135-138. 2. Wecker SS: Pene gemino quidam, Obs Med Admirab Moust Lib Y: De partibus Genitalibus, Francoforth, 1609. 3. Hollowell JG: Embryologic considerations of diphallus and associated anormalies, J Urol 117:728, 1977. jmapar@prodigy.net.mx.