The stroke phenotype of these lines clearly depends on the genomic configuration of the inserted chromosomal segment belonging to STR1, with evidence that the chromosomal fragment carrying UCP2 significantly interferes with stroke occurrence.5 Herein, we report that the introgression of the stroke-prone STR1 chromosomal segment (carrying UCP2) within the stroke-resistant genomic background led to a suppression of UCP2 expression in contrast to the upregulation of the SHRSR strain. This evidence concerns the gene MMP3 and Stroke.