This experiment was conducted to study the effects of breed, diet and sex on expression of growth-related genes in Nigerian goats. A total of 36 weaner goats of two breeds (West African dwarf, n = 18
9 males + 9 females) and Red Sokoto goats, n = 18
9 males + 9 females) of about 3-4 months of age were used for the experiment. A 2 × 3 × 2 factorial experiment comprising 2 breeds, 3 diets groups and 2 sexes in a Completely Randomized Design was used. The data for gene expression and their interaction effects were all analysed using Statistix Analytical software, file version 8.0. Results showed that breed, diet and breed × diet interaction had significant (P <
0.05) effect on IGF-1 tissue expression. Sex had significant (P <
0.05) effect on myostatin tissue expression. Breed × diet interaction had no significant (P >
0.05) effect on MSTN expression in the tissue of goats. The results for breed × sex interaction had no significant (P >
0.05) effect on the level of IGF-1 expression in the tissue of goats but had significant (P <
0.05) effect on myostatin gene. Red Sokoto breed is recommended over West African dwarf breed while RS × 50%DS + 50%GH is recommended for IGF-1 expression. There is need for further research to fully understand the IGF-1 and MSTN gene expression levels in various tissues and organs of goats at different stages of growth.