Stavropoulos, Dimitri J.

We report on 19 individuals with a recurrent de novo c.607C>T mutation in PACS1. This specific mutation gives rise to a recognizable intellectual disability syndrome. There is a distinctive facial appearance (19/19), characterized by full and arched eyebrows, hypertelorism with downslanting palpebral fissures, long eye lashes, ptosis, low set and simple ears, bulbous nasal tip, wide mouth with downturned corners and a thin upper lip with an unusual “wavy” profile, flat philtrum, and diastema of the teeth. Intellectual disability, ranging from mild to moderate, was present in all. Hypotonia is common in infancy (8/19). Seizures are frequent (12/19) and respond well to anticonvulsive medication. Structural malformations are common, including heart (10/19), brain (12/16), eye (10/19), kidney (3/19), and cryptorchidism (6/12 males). Feeding dysfunction is presenting in infancy with failure to thrive (5/19), gastroesophageal reflux (6/19), and gastrostomy tube placement (4/19). There is persistence of oral motor dysfunction. We provide suggestions for clinical work‐up and management and hope that the present study will facilitate clinical recognition of further cases. © 2016 Wiley Periodicals, Inc.

Background The contribution of copy-number variation (CNV) to disease has been highlighted with the widespread adoption of array-based comparative genomic hybridisation (aCGH) and microarray technology. Contiguous gene deletions involving ANKRD11 in 16q24.3 are associated with autism spectrum disorder (ASD) and intellectual disability (ID), while 16q24.1 deletions affecting FOXF1 are associated with congenital renal malformations, alveolar capillary dysplasia, and various other abnormalities. The disease associations of deletions in the intervening region, 16q24.2, have only been defined to a limited extent. Aim To determine whether deletions affecting 16q24.2 are correlated with congenital anomalies. Methods 35 individuals, each having a deletion in 16q24.2, were characterised clinically and by aCGH and/or SNP-genotyping microarray. Results Several of the 35 16q24.2 deletions identified here closely abut or overlap the coding regions of FOXF1 and ANKRD11, two genes that have been previously associated with the disease. 25 patients were reported to have ASD/ID, and three were found to have bilateral hydronephrosis. 14 of the deletions associated with ASD/ID overlap the coding regions of FBXO31 and MAP1LC3B. These same genes and two others, C16orf95 and ZCCHC14, are also included in the area of minimal overlap of the three deletions associated with hydronephrosis. Conclusions Our data highlight 16q24.2 as a region of interest for ASD, ID and congenital renal malformations. These conditions are associated, albeit without complete penetrance, with deletions affecting C16orf95, ZCCHC14, MAP1LC3B and FBXO31. The function of each gene in development and disease warrants further investigation.