Abstract: The present invention relates to methods for stimulating muscle growth and/or for inhibiting muscle atrophy in a subject suffering from or predisposed to having a muscle wasting disease by administering an agent that increases the expression of the runx1 gene or gene product in an individual. The invention further provides a biomarker for a muscle wasting disease or condition and methods for screening or diagnosing a subject having, or predisposed to having, a muscle wasting disease by measuring the level of expression of the runx1 gene, or its target genes or gene products in an individual. The invention further relates to the preparation of pharmaceutical compositions using agents that may aid in muscle growth and that may prevent or inhibit muscle atrophy by increasing the expression and/or activity of the runx1 gene and/or gene product.

Abstract: The invention provides transgenic non-human animals and transgenic non-human mammalian cells having at least one functionally disrupted lymphocyte transduction locus, particularly a CD4 locus, targeting constructs used to produce such transgenic stem cells and animals, methods and targeting constructs for inactivating or suppressing expression of endogenous lymphocyte transduction gene loci, transgenes encoding heterologous lymphocyte transduction proteins, and nonhuman animals that express a human lymphocyte transduction protein and lack expression of a cognate murine lymphocyte transduction protein.