Sunday, July 12, 2009

More on genes from China

I reported on this genetics article from China, now published in a Western journal: J Hum Genet. 2009 Jul 10 which should increase our confidence in its quality. The research suggests a link between genes active in the dopamine (a brain chemical) system and stuttering. Dopamine acts on the connections between neurons in two ways via the level of dopamine and via the level of dopamine receptors that modulate the dopamine level. Jerry Maguire suggests to me that the result
helps to support their dopamine hypothesis of stuttering that an over activity at D2 receptors contributes to stuttering. Many of our successful medications specifically target the D2 receptor i.e. risperidone, olanzapine, aripiprazole and others.
I also emailed Dennis Drayna but he didn't reply.

Here is the abstract:

Association between dopaminergic genes (SLC6A3 and DRD2) and stuttering among Han Chinese.

Lan J, Song M, Pan C, Zhuang G, Wang Y, Ma W, Chu Q, Lai Q, Xu F, Li Y, Liu L, Wang W.

Department of Genetics, College of Life Sciences, Graduate University of Chinese Academy of Sciences, Beijing, PR China.

Normal function of the dopaminergic system is necessary for speech fluency. There was evidence that the activities of dopamine transporter (DAT) and dopamine D2 receptor (DRD2) could be altered in people with speech disfluency. This study aims to ascertain the possible correlation between two dopaminergic genes (SLC6A3 and DRD2) and disorder of speech fluency, and to determine the allelic frequencies of the five single-nucleotide polymorphisms (SNPs) (rs2617604, rs28364997, rs28364998 in SLC6A3 and rs6275, rs6277 in DRD2) among Han Chinese patients with this disorder. A sample of 112 patients with speech disfluency and 112 gender-matched controls were included in this case-control study. The results show that the presence of C allele at rs6277 in DRD2 gene is associated with increased susceptibility to the disorder, whereas T allele is protective. Haplotype 939T/957T is also a protective factor. Journal of Human Genetics advance online publication, 10 July 2009; doi:10.1038/jhg.2009.60.


Kanstantsin said...

"The Journal of Human Genetics is the official journal of the Japan Society of Human Genetics"

not really "western" :) but at least it's in English and have impact factor (though not very high - 2,3). so data should be reliable.

Now if I were one was this chinese researchers, I would devide studied PWS in groups, according to which variant of gene they have, And would give them drugs targeting this dopamine receptor and see what happens..
And if I were one of these guys who organized Pagoclone clinical tests - I would make the same genetics tests on PWS and compare the results with Pagoclone efficiency.

Rob said...

great work man, keep it up!

Tom Weidig said...

Hi Kanstantsin,

Thanks for your comments!

The journal just sounded Western! But at least the data is in English and more reliable.

It is my understanding that the Pagaclone trials include blood tests with gene tests, at least it was planned.

Best wishes,

ac said...

Interesting article - thanks.

What did they use to measure the association?

Anonymous said...

Then why do some stutterers recover as they grow older. Is their stuttering caused by somthing else.

Thanks for the great work.