TP53 and osteoporosis: (2004) developed another mouse model expressing a shorter p53 isoform lacking exons from 1 to 3 that produced a truncated and Mdm2‐insensitive p53 protein of 44 KDa called p44tg. These mutant animals show increased resistance to spontaneous carcinogenesis but present a reduction in life expectancy and premature development of diseases such as osteoporosis and tissue atrophy.