Abnormal brain MRI signal in 18q-syndrome not due to dysmyelination

Patchy white matter hyperintensity in ring chromosome 18 syndrome

“…The myelinated axons and myelin thickness remained normal when MBP expression was >50% of normal . Basedon this experimental observation, 18q‐ or ring chromosome 18 syndrome patients with 50% gene expression by the one remaining copy, have regular myelination in the central nervous system . MBP is one of the components of myelin in the peripheral nervous system.…”

“…studied seven patients, including a boy aged 2 years, whose MRI showed abnormal myelination, but the MRI itself was not included in the article. The cerebral abnormalities relating to ring chromosome 18 syndrome have been considered to resemble those of 18q‐ syndrome . White matter abnormalities in 18q‐ syndrome are seen in up to 75% of patients and have been regarded as hypomyelination due to the deletion of the gene for MBP production, which is located at 18q23.…”

“…reported one case, and Tanaka et al . reported another; in both cases, imaging indicated mild symmetrical white matter T2 hyperintensity . Stankiewicz et al .…”

“…Previously reported brain magnetic resonance imaging (MRI) abnormalities in only two patients included diffuse hyperintensity in the white matter, which has been regarded as hypomyelination because the gene for myelin basic protein (MBP) production is located on the long arm of chromosome 18 …”

Neurochemistry in shiverer mouse depicted on MR spectroscopy

“…Shiverer mice exhibit progressive tremors and tonic seizures early in life, which cause their premature death between 3 and 5 months of age. The animals had free access to food and water and were kept under standard laboratory conditions of [22][23] C room temperature, around 50% humidity, and a 12:12 hour light/dark cycle. Immediately prior to and during the MRI scanning, all mice were anesthetized with 2% isoflurane (Mylan Japan, Japan).…”