By database mining, Peeters et al. (2003) identified a gene family related to p53-activated gene-26 (PA26), which they termed the sestrin family. Sequence alignment of human and mouse sestrin protein family members showed that the gene family is highly conserved. The SEST3 gene encodes a deduced 492-amino acid protein.
Using FISH, Peeters et al. (2003) confirmed the localization of the human sestrin genes PA26, SEST2 , and SEST3 to chromosomes 6q21, 1p35.3, and 11q21, respectively. Using the same method, they mapped the mouse Pa26, Sest2, and Sest3 genes to syntenic regions on chromosomes 4, 9, and 10, respectively.