of either exons and 20 intron-exon boundary nucleotides of a panel of 525 re- cessive disease genes [Children's Mercy Hospital Diagnostic panel 1 (CMH-Dxl)] or the exome (Table 2). CMH-Dx1 comprised 8813 exonic and intronic targets, totaling 2.1 million nucleotides (table SI) (2, 33). The exome and CM