The pacific oyster Crassostrea gigas is a bivalve mollusc belonging to the Lophotrochozoa group. Following numerous introductions, its geographical distribution is currently very wide and it represents the world’s largest aquaculture production.
C. gigas is a sentinel species of choice for understanding the evolution of coastal and estuarine ecosystems, where oyster populations are subject to changing environmental conditions and suffer significant mortality rates related mainly to stress and disease. These characteristics motivated the development of research into the biology of C. gigas. In addition, its high fecundity and the high degree of sequence polymorphism of its DNA, make C. gigas an interesting model for population biology and genetics.
In recent years, the genomic resources available for C. gigas have increased with the generation of 56268 EST assembled into 31952 contiguous EST hosted in a database obtained through the European projects Aquafirst and Marine Genomics Europe and the Genoscope project (CEA, Evry, France). As of today, the focus is on diversifying techniques for functional gene exploration: although classical functional genetics approaches, such as mutagenesis, are not yet available, the technique of RNA interference (RNAi) has recently been developed to study gene function.
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Wang X, Xu W, Wei L, et al. Nanopore Sequencing and De Novo Assembly of a Black-Shelled Pacific Oyster (Crassostrea gigas) Genome. Front Genet. 2019;10:1211. Published 2019 Nov 22. doi:10.3389/fgene.2019.01211