Genetics of growth in blue mussels: family and enzyme-heterozygosity effects

✍ Scribed by A. L. Mallet; E. Zouros; K. E. Gartner-Kepay; K. R. Freeman

• Publisher: Springer-Verlag
• Year: 1986
• Tongue: English
• Weight: 704 KB
• Volume: 92
• Category: Article
• ISSN: 0025-3162
• DOI: 10.1007/bf00392507

✦ Synopsis

Shell length and electrophoretic heterozygosity at six enzyme loci were scored in juveniles of 30 hatchery-grown families and in adults of 10 field-grown families of the blue mussel Mytilus edulis. A total of 4 809 offspring were scored. We found no consistent pattern in the correlations between shell length and enzyme heterozygosity among sibs within families. However, a significant family effect on shell length was observed, suggesting an influence of background genotype on this character. A family effect on viability was also observed. When the environment and family effects were accounted for, a small positive correlation between heterozygosity and shell length at the juvenile stage remained. This correlation was significant in one of the three experiments. No such correlation was evident at the adult stage. Our interpretation of these results is that electrophoretic alleles appear to have no direct or independent effect of their own on growth. We suggest that the negative correlation of homozygosity with these characters, seen in natural populations, results from homozygosity for hidden recessive deleterious genes with which the electromorphs are in a steady state of quasilinkage disequilibrium.