Micro RNA 155, (miRNA-155) is over expressed in Down Syndrome and that this does indeed damage the Blood Brain Barrier. This is a new development in the study of genes and their relationship to disease. Very serious damage is caused by these miRNAs such as TMD, Leukemia, the failure of neurogenesis, etc. The following is a collection of supportive studies.
WHAT ARE miRNAS? http://www.exiqon.com/what-are-microRNAs
“We have briefly discussed that miRNA-155 causes damage to the blood brain barrier when over expressed. This post is a long one but your child’s future may be affected by the information you find here. There are 5 microRNA genes mapped to C21 with crossover activity on other genes.”
At present, five miRNA have been identified that are mapped to chromosome 21 and upregulated in DS. MiRNAs-155, 125b, 99a, 802 and Let 7. Three of them, Let 7, miRNA-99a and miRNA-802 are tumor suppressors or regulate tumor suppressors. This explains why people with Trisomy 21 rarely develop solid tumor malignancies.
MICRO-RNAs – SEE PARTICULARLY THE SECTION ON DOWN SYNDROME
The Role of MicroRNAs in Human Diseases http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3558168/
Abnormal MicroRNA Expression in Ts65Dn Hippocampus and Whole Blood: Contributions to Down Syndrome Phenotypes http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3254042/
“MiRNA-155 WHEN UPREGULATED DAMAGES THE BLOOD BRAIN BARRIER” http://www.ncbi.nlm.nih.gov/pubmed/24604078
“Though it is known that miRNA-155 is upregulated in DS scientists have not bothered to relate this to DS but to other, more ‘acceptable’ neurological disorders. This is very sadly a theme in DS research where monies are spent examining serious problems in diseases that ‘normal’ people fall victim to. I have always found it unacceptable that new findings in DS are touted as potentially offering insight to cures for diseases in non DS patients. This is obvious in DS research focused on therapies for non DS Alzheimer’s disease and now with miRNA research.” – Dixie Lawrence, Biochemist and T21 researcher