A genomewide association study for bronchopulmonary dysplasia using DNA pooling

Bronchopulmonary dysplasia (BPD) is the most common chronic respiratory disease in premature infants. Recent studies have highlighted the contribution of genetic factors to BPD susceptibility. Our aim was to identify the genetic variants associated to BPD, through a genomewide association study. Two discovery series were performed, using a DNA pooling-based strategy in Caucasian and black African neonates. DNA pooling studies were performed in two discovery series. The first discovery series was made up of 22 Caucasian infants with BPD and 76 Caucasian controls. The second discovery series was composed of 21 black African infants with BPD and 86 black African controls. Equimolar amounts of each DNA sample were then added to either the case or control pool, for each series. To control for experimental errors, several independent sets of pools were constructed. Concerning the Caucasian series, 3 sets of identical pools were constructed with one made in double quantity in order to hybridize it twice, which led to 4 independent replicates. Concerning the black African series, 4 sets of identical pools were constructed and each was hybridized once, leading also to 4 independent replicates. Genotyping was performed using the Infinium II Illumina HumanHap300 Genotyping BeadChip array for the Caucasian population and the Illumina HumanHap650Y array for the black African population. Each replicate was hybridized once which led to 4 arrays for each case and control pools and for each population. A total of 16 arrays were performed. technical replicate: Sample 1, Sample 2, Sample 3, Sample 4 technical replicate: Sample 5, Sample 6, Sample 7, Sample 8 technical replicate: Sample 9, Sample 10, Sample 11, Sample 12 technical replicate: Sample 13, Sample 14, Sample 15, Sample 16