Association of the expression levels in the longissimus muscle and a SNP in the CDC10 gene with marbling in Japanese Black beef cattle

- The CDC10 gene is related to cellular proliferation and located in a QTL region for marbling trait in Japanese Black cattle.
- The CDC10 expression level is positively correlated with marbling trait in Japanese Black cattle.
- The CDC10 expression level is higher in high-marbled Japanese Black steers than low-marbled Japanese Black steers.
- A SNP (NCBI_ss1388116468) in the promoter region of the CDC10 gene is associated with marbling trait.
- The CDC10 SNP may be useful for effective marker-assisted selection to increase the level of marbling.

The septin 7 (CDC10) gene, involved in cellular proliferation, has been previously shown to be expressed at different levels in the longissimus muscle (LM) between low-marbled and high-marbled steer groups by differential-display PCR. It is located within the genomic region of a quantitative trait locus for marbling, and thus was considered as a positional functional candidate gene for marbling. In this study, we showed that the CDC10 expression levels in the LM were positively correlated with marbling in Japanese Black (JB) steers (P < 0.0001). Further, an association analysis indicated that a SNP in the promoter region of the CDC10 gene was associated with marbling using 99 JB sires (P = 0.03) and 542 JB paternal half-sib progeny steers from a sire homozygous for G allele at the SNP (P < 0.0001). These findings suggest possible effects of the expression levels in the LM and the SNP of the CDC10 gene on marbling in JB cattle.