This track indicates alternative sequence from the GRCh37 reference sequence. Items marked in blue have alternate haplotypes (score=500). Items marked in red indicate areas of the sequence that have been corrected and will update to new sequence in the next release (score=1000).
The locations were established by NCBI and specified in the ALT_REF_LOCI_?/placed_scaffolds/alt_locus_scaf2primary.pos files at: Homo_sapiens/GRCh37/ and the patch2 release: NCBI FTP site.