Building upon the preceding analysis, the rationale for targeting microglia, astrocytes, oligodendrocytes, and endothelial cells in X-ALD gene therapy is justified by their high ABCD1 expression levels, as demonstrated by modern sequencing technologies, their central roles in disease progression through interconnected mechanisms, and their accessibility through cell-specific therapeutic approaches. This evidence concerns the gene ABCD1 and X-linked adrenoleukodystrophy.