of discrepancies, rs768224/tsc0075731, also has a SNP (rs10977965) in its neighboring XbaI site. When the minor allele is present at this SNP, the resulting fragment is 2,978 nucleotides in length- again, too long to be amplified. Accordingly, these two known SNPs in XbaI sites would account for 32% of the 180 observed discrepancies. Of course, a definitive test of this hypothesis would require sequencing discrepant individuals at the respective XbaI sites.
