Provided are compositions related to HSD17B13 variants, including nucleic acid molecules and polypeptides related to variants of HSD17B13, and cells comprising those nucleic acid molecules and polypeptides. Also provided are methods related to HSD17B3 variants. Such methods include methods for detecting the presence of the HSD17B13 rs72613567 variant in a biological sample comprising genomic DNA, for detecting the presence or levels of any one of variant HSD17B13 Transcripts C, D, E, F, G, and H, and particularly D, in a biological sample comprising mRNA or cDNA, or for detecting the presence or levels of any one of variant HSD17B13 protein Isoforms C, D, E, F, G, or H, and particularly D, in a biological sample comprising protein. Also provided are methods for determining a subject's susceptibility to developing a liver disease or of diagnosing a subject with liver disease.

Provided are compositions related to HSD17B13 variants, including isolated nucleic acids and proteins related to variants of HSD17B13, and cells comprising those nucleic acids and proteins. Also provided are methods related to HSD17B13 variants. Such methods include methods for modifying a cell through use of any combination of nuclease agents, exogenous donor sequences, transcriptional activators, transcriptional repressors, and expression vectors for expressing a recombinant HSD17B13 gene or a nucleic acid encoding an HSD17B13 protein. Also provided are therapeutic and prophylactic methods for treating a subject having or at risk of developing chronic liver disease.

The subject of the present invention is a process for preparing a genetically modified yeast by multicopy integration of at least four expression cassettes, allowing the production of a molecule of interest at high titer. The subject of the present invention is also yeasts transformed according to said process, and the use thereof for producing hydrocortisone.

Compositions, methods, and systems for modifying sterol metabolism in a subject is disclosed. In some embodiments, the subjects may be administered one or more mammalian cells modified to express at least one sterol degrading enzyme derived from a bacterium. In many embodiments, the cell is a macrophage or monocyte stably expressing three or more enzymes that aid in opening the ring of cholesterol. The disclosed compositions and methods may be useful in lowering cholesterol levels in a subject in need thereof. In some embodiments, the subject may have a genetic predisposition to atherosclerosis.