Aging and induced pluripotent stem cells

At present, the exact mechanism and biological basis of aging is unknown. The antagonistic pleiotropy theory and competing model of senescence explain the aging occurrence of some physiological functions of human body from different angles. The single nucleotide polymorphisms (SNPs) of genome suggest the individual’s difference of aging process is associated with SNPs-related individual’s sensitivity to diseases. As the naturally occurring DNA damages and age-associated accumulation of DNA damage as well as decline in gene expression regulation indicate individual life expectancy, whereas the shortening mechanism of telomeric terminals of chromosomes and Hayflick limit of cell division determine human life span.