Array comparative genomic hybridization in patients with congenital diaphragmatic hernia: mapping of four CDH-critical regions and sequencing of candidate genes at 15q26.1-15q26.2.
Congenital diaphragmatic hernia (CDH) is a common birth defect with a high mortality and morbidity. There have been few studies that have assessed copy number changes in CDH. We present array comparative genomic hybridization data for 29 CDH patients to identify and map chromosome aberrations in this disease. Three patients with 15q26.1-15q26.2 deletions had heterogeneous breakpoints that overlapped with the critical 4 Mb region previously delineated for CDH, confirming 15q26.1-15q26.2 as a critical region for CDH. The three other most compelling CDH-critical regions for genomic deletions based on these data and a literature review are located at chromosomes 8p23.1, 4p16.3-4pter, and 1q41-1q42.1. Based on these recurrent deletions at 15q26.1-15q26.2, we hypothesized that loss-of-function mutations in a gene or genes from this region could cause CDH and sequenced six candidate genes from this region in more than 100 patients with CDH. For three of these genes (CHD2, ARRDC4, and RGMA), we identified missense changes and that were not identified in normal controls; however, none of these alterations appeared unambiguously causal with CDH. These data suggest that CDH caused by chromosome deletions at 15q26.2 may arise because of a contiguous gene deletion syndrome or may have a multifactorial etiology. In addition, there is evidence for substantial genetic heterogeneity in CDH and diaphragmatic hernias can be non-penetrant in patients who have deletions involving CDH-critical regions.
Slavotinek
Anne M
AM
Department of Pediatrics, Division of Genetics, University of California, San Francisco, Room U585P, 533 Parnassus St, San Francisco, CA 94143-0748, USA. slovotia@peds.ucsf.edu
Moshrefi
Ali
A
Davis
Randy
R
Leeth
Elizabeth
E
Schaeffer
G Bradley
GB
Burchard
González Esteban
GE
Shaw
Gary M
GM
James
Bristow
B
Ptacek
Louis
L
Pennacchio
Len A
LA
D016022:Case-Control Studies; D002874:Chromosome Mapping; D002884:Chromosomes, Human, Pair 15; D005260:Female; D017353:Gene Deletion; D006548:Hernia, Diaphragmatic / Q000235:genetics*; D006801:Humans; D007621:Karyotyping; D008297:Male; D009693:Nucleic Acid Hybridization / Q000379:methods*; D017422:Sequence Analysis, DNA