Principal component analysis (PCA), homozygosity rate estimations, and linkage studies in humans are classically conducted through genome-wide single-nucleotide variant arrays (GWSA). We compared whole-exome sequencing (WES) and GWSA for this purpose. We analyzed 110 subjects originating from different regions of the world, including North Africa and the Middle East, which are poorly covered by public databases and have high consanguinity rates. We tested and applied a number of quality control (QC) filters. Compared with GWSA, we found that WES provided an accurate prediction of population substructure using variants with a minor allele frequency > 2% (correlation = 0.89 with the PCA coordinates obtained by GWSA). WES also yielded highly reliable estimates of homozygosity rates using runs of homozygosity with a 1,000-kb window (correlation = 0.94 with the estimates provided by GWSA). Finally, homozygosity mapping analyses in 15 families including a single offspring with high homozygosity rates showed that WES provided 51% less genome-wide linkage information than GWSA overall but 97% more information for the coding regions. At the genome-wide scale, 76.3% of linked regions were found by both GWSA and WES, 17.7% were found by GWSA only, and 6.0% were found by WES only. For coding regions, the corresponding percentages were 83.5%, 7.4%, and 9.1%, respectively. With appropriate QC filters, WES can be used for PCA and adjustment for population substructure, estimating homozygosity rates in individuals, and powerful linkage analyses, particularly in coding regions.exome sequencing | genotyping array | population structure | homozygosity mapping | linkage analysis W hole-exome sequencing (WES) has become the leading strategy for uncovering germ-line exome variants in humans. A number of gene-and variant-level methods have been proposed for the analysis of WES data to select candidate variants in rare Mendelian disorders and more common traits (1-13). These analyses benefit from the use of additional information, such as familial linkage, homozygosity rate, and ethnic background, which are commonly used in the study of inherited diseases (14-17). Genomewide single-nucleotide variant array (GWSAs) are the gold standard method for linkage analysis, because they provide maximal linkage information for the whole genome (18). GWSAs are also classically used to estimate homozygosity rate in patients, confirming or sometimes, revealing parental consanguinity through the inbreeding coefficient parameter F in particular (19,20). Population stratification can be an issue in the analysis of population-based genetic data, including WES, particularly for association studies (21-24). Population structures have been widely determined by GWSA (25, 26) in European (27), African (28, 29), Asian (30), Jewish (31), Mexican (32), and other populations (33). These analyses are mostly based on principal component analysis (PCA) (34), which can also be used to confirm or reveal the ethnicity of an individual patient (or his or her parents).U...