Effect of in ovo injection of betaine for second generation (F2) on hypothalamic expression of cholesterol metabolic genes in chickens. (A) Hypothalamic mRNA expression of SREBP2 (P = 0.03), HMGCR (P = 0.03), CYP46A1 (P = 0.02), and ABCA1 (P = 0.02). (B) Protein expression of SREBP2 (P = 0.04), HMGCR (P = 0.01), CYP46A1 (P = 0.05), and ABCA1 (P = 0.03). Values are means ± SEM, *P < 0.05, compared with control (n = 6). SREBP2, sterol response element binding protein 2; HMGCR, 3-hydroxy-3-methyl-glutaryl-CoA reductase; CYP46A1, cholesterol 24-hydroxylase; ABCA1, ATP-binding cassette subfamily A member 1.