The most frequent locus in the control group was 9p.
We have previously reported that recurrent homozygous deletions appear to specifically target MAP2K4 in primary ovarian tumors, and the gene lay in a minimal region of loss of heterozygosity (LOH) in 68% (72/106) of the cases, the second most frequent locus targeted by LOH [ 18].
Although power for larger numbers of loci was lower, it was still about 96% with 100 equi-frequent loci.
ENGAGE was estimated to have a power of 99.26% to detect a McManus model with 30 equi-frequent loci, and 98.96% with 40 loci.
The micro-deleted region was defined when 3 or more adjacent SNP markers were considered frequent LOH loci.
In this study, the frequencies of homozygous genotypes were compared with those of heterozygous genotypes between NPC cases and matched healthy controls to detect frequent LOH loci at 6p, as performed in our previous study [22].
Overall, CGH identified a complex pattern of aberrations; however, several frequent chromosomal loci of copy number change were seen.
Indeed, we observe that segmental duplications in the genome are very frequent in loci containing breakpoints of human lineage origin, as previously reported [ 10- 12].
