COMPARISON OF Callitbrix jaccbus PER3 GENE AGAINST OTHER PRIMATES

*Corresponding author e-mail; flaviacal@gmail.com Introduction: Period 3 gene (Per3) is lacking of characterization and full annotation in Callithrix jacchus , although in other primates it is known (e.g. Human). Mutations in the Period genes have strong effects on circadian rhythms and are associated with human circadian rhythms sleep disorders. And a major effort is given for a Variable Number of Tandem Repeats (VNTR) in exon 18 of h Per3. This VNTR is also associated with the diurnal preference phenotype (morningness/eveningness) and with DSPS. In marmoset the VNTR contains 7 repeats and differs from others primates (e.g. in general others primates can range in 3-5 repeats). However, the role of this Per3 VNTR is unclear. Here, we present the full characterization of Per3 gene which includes definition of exons-introns regions, search for polymorphism, identification and analysis of transposable elements and noncoding RNA, and the comparison of this VNTR with others primates. Methods: To search for length polymorphisms in VNTR region were analyzed DNA samples of 70 marmosets, 33 capuchin monkeys, one Goeldi's marmoset. In addition, we are analyzing two red howler monkeys and one wooly monkey. The DNA was extracted from blood. To get the sequence of marmoset's cDNA Per3, the primers were design based on human, chimpanzee and rat cDNAs. Total RNA was extracted from liver of a marmoset and the cDNA was made from this. After a marmoset Per3 draft contig became available in UCSC genome browser we started used the draft sequence to help with the intronic regions. But, this contig is incomplete and have differences of our exemplar. Now we started to look for SNPs in 50 marmosets by DHPLC technique in exonic regions. Results and conclusion: The entire cDNA sequence showed 4173 bp and the identity of marmoset cDNA with the human and marmoset of UCSC Per3 was 82% and 92%, respectively. More than 70% of intronic fragments were sequenced. These sequences showed up 81-89% of identity with the related sequence of the hPer3. Phred/Phrap/Consed package has been used to assembly all the gene sequence. RepeatMasker and RNAz were used for identification of TE and ncRNA, respectively. In the VNTR region, only one marmoset presents a length polymorphism (7 and 6 repeat), while the Capuchin monkeys carry two copies and Goeldi, six, but there was no polymorphisms variation in these two species. Which the Per3 sequenced and characterized we will be able to study gene-environmental interactions in an animal model as marmoset. Support: AFIP, FAPESP (CEPID). Publication History Article published online: 16 June 2026 © 2009. Brazilian Sleep Academy. This is an open access article published by Thieme under the terms of the Creative Commons Attribution-NonDerivative-NonCommercial License, permitting copying and reproduction so long as the original work is given appropriate credit. Contents may not be used for commercial purposes, or adapted, remixed, transformed or built upon. (https://creativecommons.org/licenses/by-nc-nd/4.0/) Thieme Revinter Publicações Ltda. Rua Rego Freitas, 175, loja 1, República, São Paulo, SP, CEP 01220-010, Brazil