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  Schema for Quality Scores - Cow Sequencing Quality Scores
  Database: bosTau4    Primary Table: quality    Row Count: 2,855,674
Format description: Wiggle track values to display as y-values (first 6 fields are bed6)
fieldexampleSQL type description
bin 585smallint unsigned Indexing field to speed chromosome range queries.
chrom chr1varchar(255) Reference sequence chromosome or scaffold
chromStart 0int unsigned Start position in chromosome
chromEnd 1024int unsigned End position in chromosome
name chr1.86443varchar(255) Name of item
span 1int unsigned each value spans this many bases
count 1024int unsigned number of values in this block
offset 88516663int unsigned offset in File to fetch data
file /gbdb/bosTau4/wib/qual.wibvarchar(255) path name to data file, one byte per value
lowerLimit 0double lowest data value in this block
dataRange 62double lowerLimit + dataRange = upperLimit
validCount 1024int unsigned number of valid data values in this block
sumData 39136double sum of the data points, for average and stddev calc
sumSquares 1808900double sum of data points squared, for stddev calc

  Sample Rows

Note: all start coordinates in our database are 0-based, not 1-based. See explanation here.

  Quality Scores (quality) Track Description


The Quality Scores track shows the sequencing quality score (range: 0 to 99) of each base in the assembly. The height at each position of the track indicates the quality of the base. When zoomed out to a large range, the heights reflect the averaged scores. Scores of 40 or higher reflect high confidence in the sequence (with an error rate of less than 1/10,000); scores of 20 or higher reflect reasonable confidence (of working draft quality).

This track may be configured in a variety of ways to highlight different aspects of the displayed information. Click the Graph configuration help link for an explanation of the configuration options.


The quality scores were provided as part of the cow assembly. The database representation and graphical display code were written by Hiram Clawson.