Table 1. Estimated frequency of trinucleotide repeats in the human genome. Frequencies were estimated by screening cosmid libraries. No. in genome = estimated frequency after adjustments (see text) 



Repeat Class 	Frequency     No. in Genome

   AAC     	1/1300 Kb     	  2300
   AAG     	1/2200 Kb    	  1400
   AAT      	 1/510 Kb     	  5900
   ACC     	1/5000 Kb    	   600
   ACG*    	1/2100 Kb    	  1400
   ACT         1/25000 Kb    	   120
   AGC     	1/4400 Kb    	   680
   AGG     	1/3700 Kb    	   810
   ATC     	1/3100 Kb    	   970
   CCG*    	1/1500 Kb    	  2000



* not corrected for n > 7