Transcriptome Analysis of The Liver Tissue in Mutton with Different Tenderness

Lamb tenderness is a very important characteristic in determining the quality and level of public acceptance in consuming meat. Genetic improvement of the tenderness needs to be investigated in an effort to produce lamb with a high level of tenderness. Genetic improvement through the RNA deep-sequencing technology can be used to understand the mechanism of the relationship between tenderness traits and its relation to good quality lamb meat. This study was aimed to improve the quality of lamb meat with a high level of tenderness and its relationship to meat quality through RNA deep-sequencing. Analysis of RNA deep-sequencing profiling of 5 samples with high tenderness and 5 samples with low tenderness was carried out from 140 sheep population using the Illumina Hiseq 2500. The total number of reads produced ranged from 21.37 to 25.37 million bases with a mean value of 22.90 million bases. A total of 328 genes could be detected differences in gene expression (DEG), namely 110 genes with high expression and 218 genes with low expression. Pathway analysis showed steroid hormone biosynthesis as the dominant pathway for differences in the tenderness level of lamb meat. Gene expression analysis identified candidate genes TP53INP1, CYP2E1, HSD17B13, ADH1C, and LPIN1 showed high expression in influencing tenderness, while the top genes that showed low expression included ANGPTL2, IGFBP7, FABP5, OLFML3, and THOC5. Polymorphism and association analysis revealed that mutation in OLFML3, ANGPTL2, and THOC5 genes could be potential markers for the tenderness in sheep. These different genes and pathways may have an impact on gene activity that causes variation in tenderness and can be used as genetic markers in sheep. However, further validation is needed to confirm the effect of this genetic marker on other sheep populations so that it can be used in selection for selecting meat with high tenderness for sheep breeding programs.