Many clinical phenotypes occur sporadically despite genetics contributing partly or entirely
to their cause. To what extent are de novo mutations the cause of sporadic traits? Locus-
specific mutation rates for genomic rearrangements appear to be two to four orders of
magnitude greater than nucleotide-specific rates for base substitutions. Widespread
implementation of high-resolution genome analyses to detect de novo copy-number
variation may identify the cause of traits previously intractable to conventional genetic …