Short case report: Xq23 deletion involving PAK3 as a novel cause of developmental delay in a 6-year-old boy

The proband is a 6-year-old boy referred to the Clinical Genetics Service with learning difficulties, autistic spectrum disorder and intellectual disability with no significant family history. He was the third child of healthy, nonconsanguineous, white European parents. There are two healthy siblings who are fit and well. He was born following a normal pregnancy at term with a birth weight of 3.486 kg (50th centile) and there were no concerns immediately after birth. He was noted to be delayed with his development; he sat up at 14 months of age, walked at 20 months of age and was delayed with his speech. He currently attends a mainstream school, but receives fulltime support and has been diagnosed with myopia and astigmatism. On examination, he was noted to have bilateral low-set ears, a bulbous tip to the nose and deepset eyes with accessory nipples (Fig. 1). His growth parameters on presentation at 6 years of age were as follows: height 123.5 cm (91st centile) and weight 25 kg (91st centile), with a head circumference of 52 cm (25th centile). © 2017 Wolters Kluwer Health, Inc. All rights reserved.