these estimates should be interpreted with caution because it has been shown that for genome-wide studies, regardless of the nature of phenotypes and the analytic methods, the estimates of locus-specific effect size tend to be inflated (62). In addition, according to the study by Cordell (63), the variance for a linkage location could be very large for a study with moderate sample size (e.g., 313 ASD families with IQ ≥ 70) and moderate locus-specific sibling relative risk.
