On first reading, differences between mice and rats in responses to missing aMECP2 gene didn’t seem to relevant to research on treating extra MECP2 gene activity in humans with MECP2 Duplication Syndrome. Later, it suddenly hit me that this could be very relevant and important. This research suggests that rats may be a better model for studying MECP2 Gene activity than mice that are currently being used in most of the studies. In a more general sense it also suggests that the role of the MECP2 gene may be species specific. Continue reading
One of the facts that suggests that it is likely that there are still many more undiagnosed cases of MECP2 Duplication Syndrome than there are diagnosed cases is that geographic, political, and socio-economic factors appear to play important factors in incidence. While some conditions and syndromes are more common in certain gene pools, there is no evidence so far that MECP2 Duplication Syndrome discriminates on the basis of race, geography, or family income. Continue reading
Although MECP2 Duplication Syndrome (or Xq28 Duplication) is correctly identified as a rare condition, available research suggests that it is not as rare as we once thought. For example, Japanese researchers published a 2014 study in Human Genome Variation that described from results of 1,250 patients with intellectual disabilities who had not received specific diagnoses. The researchers performed advance genetic testing on these 1,250 patients and found probable genetic causes for 17% of these individuals. Many different genetic conditions were found among these 17% of patients. However, one condition was found more frequently than any other. That condition was Xq28 duplication with duplication of the MECP2 gene. This suggests that MECP2 Duplication Syndrome is not nearly as rare as once believed and that many cases continue to go diagnosed.
In the words of the researchers: Continue reading
As strange as it may seem rare chromosomal disorders are quite common.
Sunday, June 7th, starts Chromosome Disorder Awareness Week. Unique is an international organization that raises awareness of chromosome disorders and their Awareness week kicks off 7 June 2015. For more information, check out their press release.
I usually don’t use this blog to comment on research that is primarily oriented toward Rett syndrome. Others with more expertise related to Rett syndrome can do a much better job of that. A recent article on Rett syndrome mice, however, deserves a bit of comment here because of its possible implications for MECP2 duplication syndrome. In “Methyl-CpG Binding Protein 2 Regulates Microglia and Macrophage Gene Expression in Response to Inflammatory Stimuli,” Cronk and colleagues raise the question of whether the role of the MECP2 gene in regulating the immune system could be central to most or all of the other problems seen in Rett syndrome. This possibility has been raised before both with Rett syndrome and MECP2 duplication syndrome, and this research provides some additional reason to take this hypothesis seriously. Continue reading
Gabel, H. W., Kinde, B., Stroud, H., Gilbert, C. S., Harmin, D. A., Kastan, N. R., et al. (2015). Disruption of DNA-methylation-dependent long gene repression in Rett syndrome. Nature. doi: 10.1038/nature14319
This new study may accelerate research on finding useful treatments for treating both Rett syndrome and MECP2 Duplication syndrome. It has been well-established that the MECP2 gene plays an important role in promoting the expression of some genes and inhibiting the expression of others. Now researchers have found that while it affects many genes, it has a greater impact on long gene expression. Continue reading
CAGE-defined promoter regions of the genes implicated in Rett Syndrome BMC Genomics 2014, 15:1177 doi:10.1186/1471-2164-15-1177
This just published article may be an important step forward in understanding MECP2 Duplication Syndrome and other MECP2 related disorders. Genes don’t work in isolation; they interact with each other. Promoter genes are the genes that turn up the activity of other genes. This article adds to the understanding of which other genes may interact with MECP2. It may help to understand why some individuals with MECP2 Duplications are more severely affected than others.
It may also provide an early start to understanding how MECP2 Duplication Syndrome can be treated to reduce the overactivity of MECP2 and possibly reduce the severity of symptoms. It is a long way from producing practical help, but it is good to know that researchers are working on these basic issues.
GEMSS: Genetics Educational Materials for School Success is a website that provides educational materials for school personnel to support the inclusion of students with genetic syndromes in the classroom. They have recently added a useful section on MECP2 duplication syndrome.
The site also includes a sections on many other genetic conditions, such as Rett syndrome and Angelman syndrome.
Regardless of the school placement of your child, this can be very helpful information to share with your child’s school.
CARRIER STATUS & TRANSMISSION OF MECP2 DUPLICATION SYNDROME
This describes how the X-linked MECP2 Duplication Syndrome is inherited across generations
First, this is not intended to be medical advice and individual factors may vary. So if you need expert help to make important reproductive decisions, consult your physician or genetic counselor. Second, I need to say I am not a geneticist and certainly not an expert, so this is just my understanding. If anyone has important additional information or corrections, let me know. I will take them under consideration. Third, even for my level of knowledge, this is a simplified explanation.
How it works
Most cases are transmitted as X-linked genetic traits from mothers to sons.
Let’s look at how this works, but first let’s just look at how chromosomes determine whether an individual is a male or female.
All females have two X chromosomes. Each female inherits one of those Xs from her mother and one X from her father.
All males have one X chromosome and one Y chromosome. Each male inherits one X from his mother and one Y from his father. Continue reading