A complementary approach to de novo genome assembly is to develop approaches that combine multiple types of information—including previously observed haplotype variation, SNVs, indels, copy number and homology information—to identify and classify haplotypes in interesting regions of the genome. One such region is around the CYP2D6 gene, which encodes an enzyme that metabolizes approximately 25% of prescription drugs and the activity of which varies substantially among individuals43–45. More than 150 CYP2D6 haplotypes have been described, some involving a gene conversion with its nearby non-functional but highly similar paralogue CYP2D7.
