Table 1.

Morphological analysis of optic nerve myelin sheaths

Genotype	Age (months)	Processes	Pathology (%)
Wild type
Animal 1	1	257	5.5
Animal 2	8	153	5.9
Animal 3	8	343	2.0
Animal 4	8	322	1.6
Animal 5	12	231	8.2
Animal 6	12	219	5.0
Total		1525	4.7* ± 0.26
L-MAG^trun
Animal 1	1	228	19.3
Animal 2	8	166	15.7
Animal 3	8	117	13.7
Animal 4	8	120	15.8
Animal 5	12	391	9.7
Animal 6	16	280	12.9
Animal 7	16	329	9.4
Animal 8	16	382	6.0
Animal 9	16	339	14.8
Total		2352	13.0* ± 0.22

Randomly selected sheaths of the optic nerves 1.75 mm anterior to the optic chiasma were analyzed for the presence of multiple wraps, lack of compaction, and redundant myelin. Multiple wraps were indicated by the presence of more than one pair of cytoplasmic tongues associated with an individual axon. Lack of compaction was indicated by the presence of cytoplasm within the myelin lamella, and redundant myelin was indicated by the presence of a compact myelin tail extending away from the axon. Electron micrographs at 35,000× were examined.
*Data are presented as mean ± SE and were analyzed using the Student t test. They are significantly different at ap value <0.001.