Five Patients With Novel Overlapping Interstitial Deletions in 8q22.2q22.3

摘要

High-resolution microarray technology has facilitated the detection of submicroscoplc chromosome aberrations and characterization of new microdeletion syndromes. We present clinical and molecular data of five patients with previously undescribed overlapping interstitial deletions involving 8q22.2q22.3. All deletions differ in size and breakpoints. Patients 1-4 carry deletions between 5.25 and 6.44 Mb in size, resulting in a minimal deletion overlap of 3.87 Mb (from 100.69 to 104.56 -Mb; hgl8) comprising at least 25 genes. These patients share similar facial dysmorphisms with blepharophimosis, telecan-thus, epicanthus, flat malar region, thin upper lip vermillion, down-turned corners of the mouth, and a poor facial movement/ little facial expression. They have a moderate to severe developmental delay (4/4), absent speech (3/4), microcephaly (3/4), a history of seizures (3/4), postnatal short stature (2/4), and a diaphragmatic or hiatal hernia (2/4). Patient 5 was diagnosed with a smaller deletion of about 1.92 Mb (containing nine genes) localized within the deletion overlap of the other four patients. Patient 5 shows a different facial phenotype and a less severe mental retardation. In Patients 1-4, COH1 is involved in the deletion (in total or in part), but none of them showed clinical features of Cohen syndrome. In two patients (Patients 2 and 4), ZFPM2 (also called FOG2, a candidate gene for congenital diaphragmatic hernias) was partly deleted. We suggest that patients with a microdeletion of 8q22.2q22.3 may represent a clinically recognizable condition characterized particularly by the facial phenotype and developmental delay. More patients have to be evaluated to establish a phenotype-genotype correlation.