Deletions of 17q12 are connected with renal cysts and maturity onset diabetes of the youthful, and have also been determined in women with reproductive tract anomalies due to Mullerian aplasia. Even though initially determined in clients with standard cognitive potential, some patients with this recurrent microdeletion syndrome have mastering difficulties. We recognized a 17q12 microdeletion in a few patients with renal cystic ailment by array comparative genomic hybridization and the phenotypic spectrum of the 17q12 microdeletion syndrome is illustrated by the description of these patients. Of two sufferers who are aged sufficient to be assessed, a single has important speech delay, autism spectrum dysfunction, and mild mastering difficulty, although the other affected person has only mild speech delay. This highlights the variability of cognitive involvement in this situation. The 3rd affected individual presented with Alagille syndrome-like features in the neonatal interval. All three patients experienced transient hypercalcemia in the neonatal interval, a obtaining that has not previously been described in this problem. Moreover, two individuals have delicate or no dysmorphism, even though 1 displays hanging facial dysmorphism in addition to small congenital anomalies. We propose that while sufferers with 17q12 microdeletion syndrome can existing with variety two diabetes or renal cysts without any dysmorphic characteristics, a subgroup could have dysmorphic attributes or current with neonatal cholestasis. Transient neonatal hypercalcemia may possibly be a characteristic of this microdeletion syndrome. © 2012 Wiley Periodicals, Inc.