Table 1.  The number of CAG repeats in the HD mice used for lifespan (L) analysis. The CAG repeat number was measured by ABI Genemapper (GM) technique (Laragen Inc. Los Angeles, CA).  The CAG numbers were derived from the PCR fragment size. The DNA fragments with trinucleotide repeats such as CAG migrate faster than the DNA fragments with random sequences.   Therefore, the CAG repeat numbers determined by GM technique is smaller than the CAG repeat numbers determined by DNA sequencing technique (SEQ), which are closer to the actual CAG repeat numbers. Overall this analysis showed that CAG repeat number remained stable, had not expanded further with breeding and did not differ between transgenic controls and runners (p>0.59).