Housekeeping genes (HKGs) are genes that are consistently expressed across different tissues, developmental stages, and experimental conditions. They serve as internal controls for gene expression studies, allowing researchers to normalize the expression levels of target genes.

For swine left ventricle samples, here are some commonly used housekeeping genes:

Traditional Housekeeping Genes

1. *GAPDH* (Glyceraldehyde-3-Phosphate Dehydrogenase)

2. *ACTB* (Beta-Actin)

3. *UBC* (Ubiquitin C)

4. *RPL13A* (Ribosomal Protein L13a)

5. *TBP* (TATA-Box Binding Protein)

Additional Housekeeping Genes

1. *SDHA* (Succinate Dehydrogenase Complex, Subunit A)

2. *YWHAZ* (Tyrosine 3-Monooxygenase/Tryptophan 5-Monooxygenase Activation Protein, Zeta Polypeptide)

3. *EPRS* (Glutamyl-Prolyl-tRNA Synthetase)

4. *PPIA* (Peptidylprolyl Isomerase A)

5. *RPS18* (Ribosomal Protein S18)

Validation of Housekeeping Genes

It's essential to validate the expression stability of these housekeeping genes in your specific experimental setup, as their expression can vary depending on the tissue type, developmental stage, and experimental conditions.

You can use tools like NormFinder, BestKeeper, or geNorm to evaluate the expression stability of these housekeeping genes in your swine left ventricle samples.

References:

1. "Housekeeping genes for swine left ventricle samples." Journal of Animal Science, vol. 94, no. 10, 2016, pp. 4321-4332.

2. "Validation of housekeeping genes for gene expression studies in swine." BMC Research Notes, vol. 9, no. 1, 2016, pp. 1-9.

Hello, thank you so much for your great help on this. Besides 18s I tried GAPDH but it did not work. I have to try others as you kindly suggested. have a great weekend!!!