CD8A and Alzheimer disease: For example, QTLs associated with exterior and production were enriched in AD pigs, such as “thoracolumbar vertebra number” and “backfat between 3rd and 4th last ribs.” In contrast, most QTLs related to health were enriched in CD pigs, such as “CD8-positive leukocyte percentage” and “CD8-negative leukocyte percentage.” Candidate genes of AD pigs were more significantly enriched in metabolic process, and CD pigs were more significantly enriched in the immune system process, which was consistent with our previous study on the selection signatures of these two lines (27).