Introduction: The 9p deletion syndrome is characterized for the presence of trigonocephaly, dysmorphism, genitourinary anomalies and developmental delay. The clinical synopsis depends on the size of the deletion.  Clinical Case: 14 month old infant with disorder of sexual development, developmental delay and dysmorphisms without trigonocephaly. Karyotype with 46,XY,del(9p22)(pter). Discussion: Sexual development disorders are very hard to diagnose, in their primary approach a karyotype is essential, most disorders can be diagnosed through this technique, other studies are also needed. Within these disorders 9p deletion syndrome is the less common, there are around 700 cases reported in the world, therefore it is important to keep contributing to the phenotype-genotype. This patient does not have trigonocephaly which bears the question of what other mechanisms are involved besides haploinsufficiency.

Introduction: The 9p deletion syndrome is a genomic disorder characterized by trigonocephaly, facial dysmorphism, genital anomalies and developmental delay. The size of the deletion in 9p is variable and there has been several attempts to propose a critical region, although there is no region yet recognized for this syndrome. The phenotype-genotype correlation could be associated to the break-points of the deletion, as well as the size and genes involved in the deleted region of 9p; since there are several genes involved in brain, embryologic, sexual development, cranial morphogenesis, transcription factors and others in the short arm of chromosome 9. This article presents a case of 9p terminal deletion with different clinical features to the consensus phenotype of 9p deletion syndrome, whose first approach was through the disorder of sexual development (DSD). Case report: Infant of 23 months referred to Genetics for clitoromegaly, without any familiar history, product of the second gestation of a normal pregnancy, without any perinatal complications and female sex assigned at birth. In the physical exam: normocephalic, facial dysmorphisms, and genital anomalies. We begin protocol for DSD finding karyotype formula of 46,XY,del(9)(p22). Discussion: It has been postulated that haploinsufficiency of the genes involved in 9p deletion combined with genomic variants are responsible for the phenotype variability, this maybe the reason why our patient does not present the classical phenotype. It is important to have a multidisciplinary team for management and follow-up with these patients for an adequate male sex assignment and treatment for any complications associated to the syndrome, if possible, in order to have a better quality of life.