Effective population size and the genetic consequences of commercial whaling on the humpback whales (Megaptera novaeangliae) from Southwestern Atlantic Ocean
Abstract Genotypes of 10 microsatellite loci of 420 humpback whales from the Southwestern Atlantic Ocean population were used to estimate for the first time its contemporary effective (Ne) and census (Nc) population sizes and to test the genetic effect of commercial whaling. The results are in agreement with our previous studies that found high genetic diversity for this breeding population. Using an approximate Bayesian computation approach, the scenario of constant Ne was significantly supported over scenarios with moderate to strong size changes during the commercial whaling period. The previous generation Nc (Ne multip...
Source: Genetics and Molecular Biology - April 16, 2018 Category: Genetics & Stem Cells Source Type: research
Association between molecular markers and behavioral phenotypes in the immatures of a butterfly
Abstract Newly hatched caterpillars of the butterfly Heliconius erato phyllis routinely cannibalize eggs. In a manifestation of kin recognition they cannibalize sibling eggs less frequently than unrelated eggs. Previous work has estimated the heritability of kin recognition in H. erato phyllis to lie between 14 and 48%. It has furthermore been shown that the inheritance of kin recognition is compatible with a quantitative model with a threshold. Here we present the results of a preliminary study, in which we tested for associations between behavioral kin recognition phenotypes and AFLP and SSR markers. We implemented two e...
Source: Genetics and Molecular Biology - April 16, 2018 Category: Genetics & Stem Cells Source Type: research
Oxytocin and arginine vasopressin systems in the domestication process
In this study, we analyzed the DNA and protein sequences of six genes of the oxytocin and arginine vasopressin systems (OXT-OXTR; AVP-AVPR1a, AVPR1b and AVPR2) in 40 placental mammals. These systems play an important role in the control of physiology and behavior. According to our analyses, neutrality does not explain the pattern of molecular evolution found in some of these genes. We observed specific sites under positive selection in AVPR1b ( ω = 1.429, p = 0.001) and AVPR2 ( ω = 1.49, p = 0.001), suggesting that they could be involved in behavior and physiological changes, including those related to the domestication...
Source: Genetics and Molecular Biology - April 16, 2018 Category: Genetics & Stem Cells Source Type: research
Evolution of DNMT2 in drosophilids: Evidence for positive and purifying selection and insights into new protein (pathways) interactions
Abstract The DNA methyltransferase 2 (DNMT2) protein is the most conserved member of the DNA methyltransferase family. Nevertheless, its substrate specificity is still controversial and elusive. The genomic role and determinants of DNA methylation are poorly understood in invertebrates, and several mechanisms and associations are suggested. In Drosophila, the only known DNMT gene is Dnmt2. Here we present our findings from a wide search for Dnmt2 homologs in 68 species of Drosophilidae. We investigated its molecular evolution, and in our phylogenetic analyses the main clades of Drosophilidae species were recovered. We test...
Source: Genetics and Molecular Biology - April 16, 2018 Category: Genetics & Stem Cells Source Type: research
How strong was the bottleneck associated to the peopling of the Americas? New insights from multilocus sequence data
In this study we use resequencing data for nine independent regions in a set of Native American and Siberian individuals and a full-likelihood approach based on isolation-with-migration scenarios accounting for recent flow between Asian and Native American populations. Our results suggest that, in agreement with previous studies, the effective size of the Native American population was small, most likely in the order of a few hundred individuals, with point estimates close to 250 individuals, even though credible intervals include a number as large as ~4,000 individuals. Recognizing the size of the genetic bottleneck durin...
Source: Genetics and Molecular Biology - April 16, 2018 Category: Genetics & Stem Cells Source Type: research
