Cockle shell colour governed by region of DNA
Detailed analysis of shellfish species points to heritable factors linked to shell colour and markings.
Scientists have pinpointed a region in the DNA of cockles which controls the colour and pattern of their shells.
The findings, in the most detailed investigation of cockle DNA to date, indicates a clear genetic factor linked to shell colour.
The insights may help breed the commercially important species to have shell colours that appeal to seafood consumers.
They could pave the way for further study to investigate the factors behind various colours and patterns found in the species, which is found along the east coast regions of the North Atlantic Ocean.
Shell colour influences
Scientists led by the University of Santiago de Compostela in Spain, and involving the Roslin Institute, built a high-density genetic map of the common cockle.
The team used this map to search for regions of the genome linked to colour variation in cockle shells.
They discovered an area of DNA containing several candidate genes linked to colour as well as stripe and circle markings.
The outcome could offer insights to enable commercial cockle breeders to produce shellfish with a desired appearance.
It may also aid further study to determine factors linked to colour, such as environmental conditions, water salinity and acidity, or risk of predation.
Their study was published in Scientific Reports.
Colours in nature can be determined by a range of factors linked to a species’ surroundings but also to their ancestry. Our detailed examination of the DNA in common cockles shows a significant hereditary factor connected to shell colour and pattern, indicating that colour conveys some importance for the species.
This study poses questions regarding the adaptive role of shell colour in cockles. Deeper studies at population level may aid understanding of the significance of the colour and pattern variation observed.
** The Roslin Institute receives strategic investment funding from the Biotechnology and Biological Sciences Research Council and it is part of the University of Edinburgh’s Royal (Dick) School of Veterinary Studies. **
Image credit: Ryan Hodnett / Wikimedia Commons