Effects of Copy Number Variations in the Plectin (PLEC) Gene on the Growth Traits and Meat Quality of Leizhou Black Goats.

The plectin (PLEC) gene is crucial in regulating muscle development and maintaining the cytoskeleton. An abnormal expression of PLEC can lead to muscle atrophy and muscular dystrophy. In a previous study, we found that Leizhou black goats exhibit abundant structural variations in the PLEC gene. However, the genetic effects of these variations on growth traits and meat quality in goats are not fully understood. In this study, three PLEC copy number variations (CNVs) were identified in a population of 417 Leizhou black goats, using quantitative polymerase chain reaction (qPCR) technology. Population distribution analysis revealed a high abundance of various types of these three CNVs. PLEC mRNA was found to be highly expressed in muscle tissue and remained consistently high from 1 month to 24 months after birth. Specifically, the gain type of CNV-1 (chr14: 81056401-81064800) showed a significant association with PLEC mRNA expression in muscle tissue (p < 0.01). The sequence of CNV-1 in PLEC shares similarities with three domain superfamilies associated with muscle development and skin disease. Furthermore, there were significant differences in chest circumference, body weight, carcass weight, the cross-sectional area of the longissimus dorsi lumbar muscle, and shear stress between different types of CNV-1 (p < 0.05). Notably, goats with the CNV-1 gain type demonstrated better phenotypic values compared to those with loss and normal types. These findings suggest that PLEC CNV-1 could play a crucial role in the growth and muscle development of Leizhou black goats, making it a potential marker for assisted selection in goat breeding.