We followed up the COL8A1 and NRXN1 findings using multiplex ligation-dependent probe amplification (MLPA; Methods S1) targeting exons 1 and 2 of COL8A1 and exons 1 to 4 of NRXN1 (with two additional probes 3′ and 5′ of this gene) (Table S2). We carried out MLPA in the Antioquian samples included in the SNP-based analysis for which DNA was available (92 cases and 142 controls). We validated the five SNP-based CNV calls (four on COL8A1 and one on NRXN1) made on these samples (Figure S5-1). MLPA identified an additional three COL8A1 deletions and two NRXN1 deletions not detected in the SNP-based CNV calls (Figures S5-2 and S5-3). No CNVs in COL8A1 or NRXN1 were detected by MLPA in the controls. We also applied the COL8A1 and NRXN1 MLPA assay to an additional set of 53 TS cases from Antioquia but did not detect further rearrangements in these individuals. Aggregating the results of the SNP-based CNV calls and MLPA (Table 4), in a total of 232 cases examined we found 7 with rearrangements in COL8A1 (all from Antioquia) and 4 in
