Abstract. Litter size is an important economic trait in the goat industry. Previous studies on the bone morphogenetic protein 15 (BMP15) gene detected some single-nucleotide polymorphisms (SNPs) such as c.963A>G that were associated with an increase in ovulation rate and litter size. The aim of this study was to conduct a meta-analysis on the effect of this polymorphism on litter size. We gathered and pooled data from five eligible published studies. To investigate the effect of c.963A>G on litter size, we utilized four different genetic models assuming dominant (GG C GA vs. AA), recessive (GG vs. GA C AA), additive (GG vs. AA) and co-dominant (GG C AA vs. GA) model of inheritance. Data were analyzed under random-effects models based on the I2 value. Furthermore, sensitivity analysis was carried out to validate the stability of results. The results showed that the c.963A>G polymorphism is associated with litter size when applying a dominant model (standardized mean difference (SMD) is 0.815, 95 % CI [0.170, 1.461], P value D 0.013) and also with an additive model (SMD D 0.755, 95 % CI [0.111, 1.400], P value D 0.022). However, the effect of c.963A>G polymorphism was not significant under recessive (SMD D 0.186, 95 % CI [−0.195, 4.259], P value D 0.339) and co-dominant (SMD D −0.119, 95 % CI [−0.525, 0.288], P value D 0.568) models. Sensitivity analysis demonstrated that dropping studies with wide confidence intervals affects overall results under the assumption of an additive model. The meta-analysis results revealed that the AA genotype could be positively connected with litter size in goats.
