The ADHD genes
ADHD treatment options
On my last post on ADHD treatment options I listed 7 different genes that have been found to be affiliated with ADHD. We will be focusing on the first listed ADHD gene in this post, the Dopamine D4 receptor gene (DRD4).
ADHD Gene #1: Dopamine D4 receptor gene (DRD4): exon III VNTR, 7-repeat
* A quick note: The"exon III VNTR, 7-repeat" bit listed above is a type of nomenclature used by geneticists to describe where on the gene the "ADHD allele" is found. Since genes can be fairly long (the "average" gene for humans is thought to be over 10,000 blocks of DNA strung together), this nomenclature is used to pinpoint both the location and what type of DNA the "ADHD form" of this gene contains. Genetic screeners will look to see if this form is present to assess your "genetic risk" for ADHD. For those of you who are interested or are familiar with genetics, I will include this information for these 7 ADHD genes, otherwise, feel free to ignore this extra info!
This gene is located on the 11th chromosome of the human genome. It is perhaps the gene most commonly affiliated with ADHD, and some studies suggest that the "ADHD allele" mentioned above is tied to nearly doubling the likelihood of an individual having ADHD. Based on research up to this point, the DRD4 gene has, potentially, the strongest correlation to ADHD for the aforementioned ADHD genes. This gene is highly associated with the frontal region of the brain (frontal subcortex), and is more affiliated with the inattentive component of ADHD than the hyperactive one, which suggests that this gene may be more tied to ADD than most of the other 6 ADHD genes listed previously.
ADHD genes and treatments
Sunday, August 31, 2008
The ADHD genes
Is ADHD genetic?
As genetic screening and genomic sequencing continue to roll along, we have made a number of interesting discoveries about ADHD and potential ADHD treatment options. A 2006 article in the Journal of Clinical Psychiatry called "Candidate Gene Studies of Attention-Deficit/Hyperactivity Disorder" by Stephen V. Faraone and Sajjad A. Khan examined some of the studies on some of the specific genes that are affiliated with ADHD. A number of these genes relate to the manufacturing, transport and modification of two key compounds involved in the brain: serotonin and dopamine. Both of these play a critical role in regulating the attention span, imbalances of one or both of these are associated with different forms of ADHD.
***These next 2 paragraphs give a basic explanation of human genetics relevant to our discussion. If you are already familiar with the terminology, these two paragraphs may be omitted. If you would like additional background information on terms such as genes, alleles, DNA and chromosomes, and how they relate to our topic of ADHD, please click here.
Before we go any further, I just want to make sure that we are on the same page as far as discussing genes related to ADHD and its potential treatment options are concerned. If you are not familiar with genetics, a gene is simply a segment of DNA that acts as a "blueprint" to the body to manufacture specific proteins that ultimately determine hair color, eye color, and even built-in-resistances to certain diseases. For humans, there are about 30,000 different genes (this number, however, is widely debatable), which are scattered throughout 23 pairs (46 total) of chromosomes. This averages out to roughly 1000 different genes per chromosome.
It is important to note that while a specific gene is extremely similar amongst different people(down to a fraction of a percent difference), there are slightly different forms of the same gene, which vary from person to person. These different forms are called alleles of the gene. These alleles can result in some huge differences among different individuals and play a major role in the great diversity of our species. If an individual has a particular form (allele) of one or more of the seven genes listed above, he or she has a higher likelihood of exhibiting ADHD behaviors. For those interested, genetic screening is available to see if an individual possesses one or more of the "ADHD alleles" for seven different genes listed below.
Seven genes that are thought to be tied to ADHD are as follows:
ADHD gene #1. Dopamine D4 receptor gene (DRD4)
ADHD gene #2. Dopamine D5 receptor gene (DRD5)
ADHD gene #3. Dopamine transporter gene (DAT)
ADHD gene #4. Dopamine beta-hydroxylase gene (DBH)
ADHD gene #5. Serotonin transporter gene (5-HTT)
ADHD gene #6. Serotonin receptor 1B gene (HTR1B)
ADHD gene#7. Synaptosomal-associated protein 25 gene (SNAP 25)
I will discuss each of these "ADHD genes" and how some of them are related to the various ADHD treatment options in more detail in my upcoming posts, so stay tuned!
Friday, August 29, 2008
Welcome to my Blog on ADHD treatment options. It is my goal to present you will information and unbiased insight into the various ADD and ADHD treatment options that are out there. The information presented in this blog has been collected from a number of published studies in the field of attention deficit disorders and the effectiveness of a number of ADHD treatment options. I will be reporting on a number of journal articles and attempt to give an earnest evaluation of their results, citing relevant sources when necessary. My main goal is to present to you the most comprehensive, accurate and honest evaluations of the many ADHD treatment options available to you or your loved ones. I welcome your comments and encourage you to subscribe to my blog. You will receive constantly-updated information as my personal research in the field continues.
This will discuss the root causes of ADD and ADHD as well as ADD and ADHD treatment options. We will evaluate some of the more well-known ADHD treatment options out there today, but will also explore some of the less well-known ADHD treatment options and their potential use as viable alternatives.