New variations identified by GM15510 ditags. (A) Comparison between ditags and fosmid sequences. Reference ditags were extracted from fosmid sequences with two restriction sites. Experimental ditags not mapped to HG18 were compared with the fosmid reference ditags to identify the variations within the fosmid sequences. (B) Summary of the results. Comparing the GM15510 experimental ditags to the reference ditags of GM15510 fosmid sequences identified 55 variations. (C) Example of an insertion variation detected by a ditag. This insertion was identified in a fosmid sequence (TI number 146956937) by a ditag AAGCTTTAACACCGTG/GTTTCTTCAAAAGCTT (See Supplemental Table 4). The tag 1 was released from a SacI site in the fosmid sequence, which does not exist in HG18. The fosmid sequences covered by the ditag contain a 24-base insertion.
