Body weight and standard length are two related traits, as long fish usually weigh more than short fish.
A QTL found for each trait was located in the same chromosomal position and was not associated with the ratio of body weight/standard length.
Thus, we concluded that the effect of the QTL is due to a gene influencing the overall growth of the fish.
The results of the canonical transformation analysis support the interpretation of one locus influencing both traits.
If the effects observed on the two traits were due to two different loci, then this marker should have significant effects on both canonical variables (Weller et al., 1996).