Penoscrotal inversion, hypospadias, imperforate anus, facial anomalies, and developmental delay: definition of a new clinical syndrome

We describe a 2-month-old boy with penoscrotal inversion, hypospadias, impe rforate anus, facial anomalies, developmental retardation, and a subtelomer ic deletion of chromosome 13q. His phenotype with anogenital malformations and characteristic facies closely resembled two unrelated patients with min ute deletions of chromosome 13q who we reported earlier, In addition, he ha d unilateral renal agenesis. We propose that these patients represent a cli nically recognizable, novel chromosomal microdeletion syndrome. The finding s indicate the presence of a major gene(s) on chromosome 13q33.2qter that r egulate(s) the migration and development of ano-reno-genital cells and orga ns. We speculate that mutations of this developmental gene(s) may also resu lt in more frequent congenital malformations (isolated hypospadias, uterus bicornis, unilateral renal. agenesis). Additional studies are needed to fur ther delineate the genetic defect.