This example shows the GENE_ID= and Pool= keys:

track name="4477685_CCP" description="Amplicon_Insert_4477685_CCP" type=bedDetail ionVersion=4.0 
chr1 2488068 2488201 242431688 . GENE_ID=TNFRSF14;Pool=2 
chr1 2489144 2489273 262048751 . GENE_ID=TNFRSF14;Pool=4 
chr1 2489772 2489907 241330530 . GENE_ID=TNFRSF14;Pool=1 
chr1 2491241 2491331 242158034 . GENE_ID=TNFRSF14;Pool=3

This example is from the CFTR designed.bed file:

track type=bedDetail ionVersion=4.0 name="CFTRexon0313_Designed" description="Amplicon_Insert_CFTRexon0313" 
chr7 117119916 117120070 CFTR_1.91108 . GENE_ID=CFTR;Pool=1;SUBMITTED_REGION=1,31 
chr7 117120062 117120193 CFTR_1.38466 . GENE_ID=CFTR;Pool=2;SUBMITTED_REGION=1 
chr7 117120186 117120304 AMPL244371551 . GENE_ID=CFTR;Pool=1;SUBMITTED_REGION=1,32