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

The plectin (<i>PLEC</i>) gene is crucial in regulating muscle development and maintaining the cytoskeleton. An abnormal expression of <i>PLEC</i> can lead to muscle atrophy and muscular dystrophy. In a previous study, we found that Leizhou black goats exhibit abundant structural variations in the <i>PLEC</i> gene. However, the genetic effects of these variations on growth traits and meat quality in goats are not fully understood. In this study, three <i>PLEC</i> 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. <i>PLEC</i> 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 <i>PLEC</i> mRNA expression in muscle tissue (<i>p</i> < 0.01). The sequence of CNV-1 in <i>PLEC</i> 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 (<i>p</i> < 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 <i>PLEC</i> 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.