Data indicates that the G1 checkpoint is activated in response to mitotic DNA damage in the presence of p53, and that the mitotic DNA damage response is connected to the G1 checkpoint by p53. If cells continue to possess damaged DNA, apoptosis is induced in a p53-dependent manner.
"An allele is a variant form of a gene. Genes come in different varieties, called alleles. Somatic cells contain two alleles for every gene, with one allele provided by each parent of an organism."- Nature .com
