18p11.31-p11.22 deletion in patient 2. Map of chromosome 18 (2,500,000-11,700,000, hg19) showing the rearrangement detected in patient 2 and overlapping deletions from the DECIPHER (D) and ISCA (I) databases. The deletions are represented with horizontal red lines. RefSeq genes are indicated in blue. The phenotype is indicated when available. The + sign indicates additional morphological features. Two genes within the deleted region in patient 2 with a high haploinsufficiency score are indicated in orange. Most of the deletions in the distal region are inherited, usually from normal parents, whereas two other de novo deletions as well as one inherited from a parent with a similar phenotype overlap the proximal region, highlighted in peach. DD, developmental delay; dn, de novo; ID, intellectual disability; inh, inherited; mat, maternal; pat, paternal; unk, unknown inheritance.