De novo del(4) (p15.32) with incomplete expression of the Wolf-Hirschhorn syndrome

A 7 7/12-year-old girl with a de novo deletion 4p15.32----pter without the typical Wolf-Hirschhorn syndrome (WHS) is presented. This observation and others from medical literature suggest that monosomy 4p15.31----4p15.32, rather than 4p16, is the cause of the typical WHS.