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Francisconi, A. F.

Publications and source records attributed to Francisconi, A. F..

2 recordsLinked to original sources

Sample Size Impact (SaSii): an R script for estimating optimal sample sizes in population genetics and population genomics studies

Obtaining large sample sizes for genetic studies can be challenging, time-consuming, and expensive. However, small sample sizes may generate biased or imprecise results. Many studies have suggested the minimum sample size necessary to obtain robust and reliable results, but it is not possible to define one ideal minimum sample size that fits all studies. Here, we aim to present SaSii (Sample Size Impact), a R script to help researchers to define minimum sample size and to indicate minimum sample size patterns for some taxa groups. The patterns were obtained by analyzing previously published datasets with SaSii and can be used as a starting point for the sample design of population genetics and genomic studies. Our results showed that it is possible to estimate an adequate sample size that accurately represents the real population and does not require the scientist to take time to write any program code, extract and sequence samples or use population genetics programs, making it easier to gather this information. We also confirmed that sample sizes of five to twenty-five for SNP and fifteen to thirty for SSR can be used for most plant species, giving a better direction for new studies.

bioinformatics↗

Complete chloroplast genomes and phylogeny in three Euterpe palms (E. edulis, E. oleraceae and E. precatoria) from different Brazilian biomes

The Brazilian palm fruits and hearts-of-palm of Euterpe edulis, E. oleracea and E. precatoria are an important source for agro-industrial production, but overexploitation requires conservation strategies to maintain genetic diversity. Chloroplast genomes have conserved sequences, which are useful to explore evolutionary questions. Besides the plastid DNA, genome skimming allows the identification of other genomic resources, such as single nucleotide polymorphisms (SNPs), providing information about the genetic diversity of species. We sequenced the chloroplast genome and identified gene content in the three Euterpe species. We performed comparative analyses, described the polymorphisms among the chloroplast genome sequences (repeats, indels and SNPs) and performed a phylogenomic inference based on 55 palm species chloroplast genomes. Finally, using the remaining data from genome skimming, the nuclear and mitochondrial reads, we identified SNPs and estimated the genetic diversity among these Euterpe species. The Euterpe chloroplast genomes varied from 159,232 to 159,275 bp and presented a conserved quadripartite structure with high synteny with other palms. In a pairwise comparison, we found a greater number of insertions/deletions (indels = 93 and 103) and SNPs (284 and 254) between E. edulis/E. oleracea and E. edulis/E. precatoria when compared to E. oleracea/E. precatoria (58 indels and 114 SNPs). Also, the phylogeny indicated a closer relationship between E. oleracea/E. precatoria. The nuclear and mitochondrial genome analyses identified 1,077 SNPs and high divergence among species (FST = 0.77), especially between E. edulis and E. precatoria (FST = 0.86). These results showed that, despite the few structural differences among the chloroplast genomes of these Euterpe palms, a differentiation between E. edulis and the other Euterpe species can be identified by point mutations. This study not only brings new knowledge about the evolution of Euterpe chloroplast genomes, but also these new resources open the way for future phylogenomic inferences and comparative analyses within Arecaceae.

evolutionary biology↗