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Biology subjects

Coutinho, L. L.

Publications and source records attributed to Coutinho, L. L..

3 recordsLinked to original sources

Genome assembly and annotation of the tambaqui (Colossoma macropomum): an emblematic fish of the Amazon River basin

Colossoma macropomum known as "tambaqui" is the largest Characiformes fish in the Amazon River Basin and a leading species in Brazilian aquaculture and fisheries. Good quality meat and great adaptability to culture systems are some of its remarkable farming features. To support studies into the genetics and genomics of the tambaqui, we have produced the first high-quality genome for the species. We combined Illumina and PacBio sequencing technologies to generate a reference genome, assembled with 39X coverage of long reads and polished to a QV=36 with 130X coverage of short reads. The genome was assembled into 1,269 scaffolds to a total of 1,221,847,006 bases, with a scaffold N50 size of 40 Mb where 93% of all assembled bases were placed in the largest 54 scaffolds that corresponds to the diploid karyotype of the tambaqui. Furthermore, the NCBI Annotation Pipeline annotated genes, pseudogenes, and non-coding transcripts using the RefSeq database as evidence, guaranteeing a high-quality annotation. A Genome Data Viewer for the tambaqui was produced which benefits any groups interested in exploring unique genomic features of the species. The availability of a highly accurate genome assembly for tambaqui provides the foundation for novel insights about ecological and evolutionary facets and is a helpful resource for aquaculture purposes.

genomics↗

Mountain lion genomes provide insights into genetic rescue of inbred populations

Introduction paragraph/AbstractAcross the geographic range of mountain lions, which includes much of North and South America, populations have become increasingly isolated due to human persecution and habitat loss. To explore the genomic consequences of these processes, we assembled a high-quality mountain lion genome and analyzed a panel of resequenced individuals from across their geographic range. We found strong geographical structure and signatures of severe inbreeding in all North American populations. Tracts of homozygosity were rarely shared among populations, suggesting that assisted gene flow would restore local genetic diversity. However, the genome of an admixed Florida panther that descended from a translocated individual from Central America had surprisingly long tracts of homozygosity, indicating that genomic gains from translocation were quickly lost by local inbreeding. Thus, to sustain diversity, genetic rescue will need to occur at regular intervals, through repeated translocations or restoring landscape connectivity. Mountain lions provide a rare opportunity to examine the potential to restore diversity through genetic rescue, and to observe the long-term effects of translocation. Our methods and results provide a framework for genome-wide analyses that can be applied to the management of small and isolated populations.

evolutionary biology↗

Association of predicted deleterious single nucleotide polymorphisms with carcass traits in meat-type chickens

In previous studies, we used genome wide association (GWAS) to identify quantitative trait loci (QTL) associated with weight and yield of abdominal fat, drumstick, thigh and breast traits in chickens. However, this methodology assumes that the studied variants are in linkage disequilibrium with the causal mutation and consequently do not identify it. In an attempt to identify causal mutations in candidate genes for carcass traits in broilers, we selected 20 predicted deleterious SNPs within QTLs for association analysis. Additive, dominance and allele substitution effects were tested. From the 20 SNPs analyzed, we identified six SNPs with significant association (p-value <0.05) with carcass traits, and three are highlighted here. The SNP rs736010549 was associated with drumstick weight and yield with significant additive and dominance effects. The SNP rs739508259 was associated with thigh weight and yield, and with significant additive and allele substitution effects. The SNP rs313532967 was associated with breast weight and yield. The three SNPs that were associated with carcass traits (rs736010549, rs739508259 and rs313532967) are respectively located in the coding regions of the WDR77, VWA8 and BARL genes. These genes are involved in biological processes such as steroid hormone signaling pathway, estrogen binding, and regulation of cell proliferation. Our strategy allowed the identification of putative casual mutations associated with muscle growth.

genetics↗