Recently, several GWAS have begun to consider genomic copy number variations (CNVs) in addition to SNPs as possible targets for association with a phenotype [107,108]. CNVs are defined as inherited duplications and deletions of kilo- to mega-base lengths of DNA and they have been shown to be present in various numbers in all individuals. CNVs have been detected in locations covering ~12% of the genome [109,110]. On a nucleotide by nucleotide basis, CNVs have therefore a higher polymorphic yield than the set of SNPs. Recent technological advances in both the hardware and software required to detect and analyze CNVs have begun to make the consideration of CNVs by a GWAS significantly more mainstream [107,111,112]. First round studies have shown CNVs to be associated with various phenotypes and disease states, including glomerulonephritis [108,113], subarachnoid hemorrhage [108], BMI [99], and even cultural dietary preferences [114]. These associations, if causative, may be due to the effects of CNVs on gene dosing, or due to their possible disruption or alteration of transcription factor binding sites, micro-RNAs, or local chromatin architecture. Additionally, several authors have
