GLOD4 and Alzheimer disease: However, relative levels of GLOD4 mRNA isoforms were significantly reduced in AD brains: from 10.31 to 3.83 (by 63%) for GLOD4_1 mRNA, from 1.00 to 0.51 (by 49%) for GLOD4_2 mRNA, and from 1.10 to 0.30 (by 73%) for GLOD4_3 mRNA (Fig. 1A).