GATK reported AD and DP
 

I am using Unified Genotyper for SNP calling. I find that the reported Allele depths and read depths seem much lower than expected (with and without the base quality recalibration). I did the alignment using CLC bio and have a SNP file from CLC bio which reports the coverage at the SNP position of reads that passed the quality filter. I understand the reported coverage values may not be exact but for equivalent quality scores, I find the DP from GATK to be 10% or 20% of the CLC bio coverage. Has anyone else seen this? Does GATK scale down the coverage?

it turned out I had to set Downsampling to None. My AD and DP were under reported due to the downsampling.